Neuraxial anaesthesia and peripheral nerve blocks during the COVID-19 pandemic: a literature review and practice recommendations.

Coronavirus disease 2019 (COVID-19) has had a significant impact on global healthcare services. In an attempt to limit the spread of infection and to preserve healthcare resources, one commonly used strategy has been to postpone elective surgery, whilst maintaining the provision of anaesthetic care for urgent and emergency surgery. General anaesthesia with airway intervention leads to aerosol generation, which increases the risk of COVID-19 contamination in operating rooms and significantly exposes the healthcare teams to COVID-19 infection during both tracheal intubation and extubation. Therefore, the provision of regional anaesthesia may be key during this pandemic, as it may reduce the need for general anaesthesia and the associated risk from aerosol-generating procedures. However, guidelines on the safe performance of regional anaesthesia in light of the COVID-19 pandemic are limited. The goal of this review is to provide up-to-date, evidence-based recommendations or expert opinion when evidence is limited, for performing regional anaesthesia procedures in patients with suspected or confirmed COVID-19 infection. These recommendations focus on seven specific domains including: planning of resources and staffing; modifying the clinical environment; preparing equipment, supplies and drugs; selecting appropriate personal protective equipment; providing adequate oxygen therapy; assessing for and safely performing regional anaesthesia procedures; and monitoring during the conduct of anaesthesia and post-anaesthetic care. Implicit in these recommendations is preserving patient safety whilst protecting healthcare providers from possible exposure.

Association of obesity with failure of ultrasound-guided axillary brachial plexus block: a two-centre, prospective, observational, cohort study.

The objective of this study was to evaluate whether the failure rate of ultrasound-guided axillary brachial plexus block is similar in obese patients compared with non-obese patients when performed as the primary anaesthetic technique. We recruited 105 obese (body mass index ≥ 30 kg.m-2 ) and 144 non-obese patients to this prospective, observational, cohort study conducted at two Canadian centres. A perineural technique of axillary brachial plexus block was performed using 30 ml ropivacaine 0.5% under real-time ultrasound guidance. Sensory and motor block assessment was carried out every 5 min until 30 min after block completion in all four terminal nerve distributions (radial, median, ulnar and musculocutaneous nerve). A composite score consisting of three sensory points and three motor points was used for assessment in each nerve distribution. A failed block was defined as a score of less than 14 points out of a possible 16 points, or a sensory block score less than 7 out of 8 points 30 min after block completion. Thirty minutes after block completion, obese patients had a higher failure rate of 33.7% (34/101) compared with 17.8% (24/135) for non-obese patients, with a failure rate difference (95%CI) of 15.9% (6.4-27.1%) between the groups. The median (IQR [range]) time to achieve a successful block in obese patients was 25 (20-30 [5-30]) min, compared with non-obese patients at 20 (15-30 [5-30]) min (p = 0.003). Despite a higher sensory-motor failure rate as per the composite score, the axillary brachial plexus block provided adequate surgical anaesthesia as indicated by a low need for conversion to general anaesthetic in obese (8.6%) and non-obese patients (7.0%; p = 0.656). This study showed that despite ultrasound guidance, obese patients had a slower onset time and higher axillary brachial plexus block failure rate at 30 min compared with non-obese patients.

Comparative evaluation of the visibility and block characteristics of a stimulating needle and catheter vs an echogenic needle and catheter for sciatic nerve block with a low-frequency ultrasound probe.

BACKGROUND: Clear visibility of the needle and catheter tip is desirable to perform safe and successful ultrasound-guided peripheral nerve blocks. This can be challenging with deeper blocks in obese patients. This study compared the visibility of echogenic and non-echogenic block needles and catheters in proximal sciatic blocks when performed with a low-frequency curved probe. METHODS: Seventy-eight patients undergoing total knee joint arthroplasty were randomized to receive an ultrasound-guided continuous sciatic nerve block using either a non-echogenic needle and stimulating catheter or an echogenic needle and echogenic non-stimulating catheter. Block needles in both groups were placed using both neurostimulation and ultrasound guidance, after which the catheter was positioned using either neurostimulation alone (Stimulating group) or imaging alone (Echogenic group). Three anaesthetists blinded to group allocation graded video clips recorded during the blocks for nerve, needle and catheter visibility. Performance characteristics and block parameters were also compared. RESULTS: No significant differences between the two groups were observed with regard to needle or catheter visibility (P=0.516). The Stimulating group required more needle redirections (P=0.009), had a longer procedure time [Echogenic median 274 s vs Stimulating 344 s (P=0.016)], and resulted in greater patient discomfort (P=0.012). There were no significant differences between the two groups in terms of block onset or completion time. CONCLUSIONS: Use of echogenic needles and catheters reduced procedure time and patient discomfort compared with a stimulating catheter system. There were no differences in the visibility scores of the two systems. CLINICAL TRIAL REGISTRATION: CTR Protocol ID: R-11-495, Clinical Trials.Gov ID: NCT 01492660.

The introduction of a surgical safety checklist in a tertiary referral obstetric centre.

BACKGROUND Surgery-related adverse events remain a significant and often under-reported problem. In a recent study, the introduction of a perioperative checklist by the WHO reduced deaths and complications by 46% and 36% respectively. The authors wished to evaluate the introduction of a surgical safety checklist in a busy obstetric tertiary referral centre by assessing staff attitudes, checklist compliance and effects upon patients. METHODS A questionnaire-based assessment was performed on staff working in obstetric theatres before and after the introduction of the surgical safety checklist. Checklist compliance was assessed at 3 months and 1 year. Patients were asked questions relating to the performance of the surgical safety checklist in order to evaluate any anxiety caused. RESULTS Non-medical staff were significantly more likely than medical staff to feel familiar with other team members both before (p<0.001) and after (p=0.03) the introduction of the checklist. 69.6% of all staff felt that interprofessional communication had improved following the introduction of the checklist. Compliance with pre- and postoperative checks was 61.2% and 67.6%, respectively, improving to 79.7% and 84.7% after 1 year. Although the majority of patients were aware of the checks being performed, this did not provoke anxiety. CONCLUSION Following consultation with staff and patients, the authors managed to institute and sustain the performance of a surgical safety checklist for elective cases in obstetric theatres. While significant progress has been made, the authors recognise that further work is required in order to further evaluate and optimise this process.

Evaluation of M43B Lumbar puncture simulator-II as a training tool for identification of the epidural space and lumbar puncture.

The identification of the epidural space, insertion of an epidural catheter and lumbar puncture are advanced technical skills that can be challenging to teach to novice anaesthetists. The M43B Lumbar puncture simulator-II (Limbs & Things Ltd., Sussex Street, Bristol, UK) is a teaching aid designed for epidural and spinal insertion. The aim of this study was to determine if experienced anaesthetists thought this simulator may be a useful tool for training novice anaesthetists in these procedures. Experienced anaesthetists performed an epidural insertion followed by a lumbar puncture procedure on the simulator model. Various aspects of both epidural and lumbar puncture insertions were scored by the anaesthetists for likeness to a real patient using a Likert scale (0--strongly disagree; 1--disagree; 2--neither agree nor disagree; 3--agree; 4--strongly agree). The simulator was found to be life-like for most aspects of epidural insertion. Median (IQR [range]) scores were: iliac crests 3.0 (3.0-3.2 [3-4]); spinous processes 3.0 (3.0-3.2 [2-4]); skin puncture 3.0 (3.0-3.0 [1-4]); subcutaneous tissues 3.0 (2.7-3.0 [1-4]); and loss of resistance 3.0 (3.0-4.0 [3-4]). The scores for supraspinous ligament 2.0 (1.0-3.0 [0-3]), interspinous ligament 2.5 (1.7-3.0 [0-3]) and ligamentum flavum 2.0 (1.0-3.0 [0-4]) were borderline for life-likeness. The volunteers found threading of the epidural catheter difficult and rated it unlike a real patient (score 1.0 (0.2-2.0 [0-3])). During lumbar puncture, dural puncture scored 3.0 (3.0-4.0 [2-4]) and intrathecal injection scored 2.5 (1.0-3.0 [1-4]). However, the overall impression was that the simulator could be a useful tool for training of both epidurals (score 3.0 (3.0-4.0 [3-4])) and spinals (score 3.0 (3.0-3.5 [2-4])).

Randomized crossover comparison between the i-gel and the LMA-Unique in anaesthetized, paralysed adults.

BACKGROUND: The i-gel differs from other supraglottic airway devices, in that it has a softer, non-inflatable cuff. This study was designed to compare the performance of the i-gel and the LMA-Unique (LMA-U) when used during anaesthesia in paralysed patients. METHODS: Both devices were studied in 39 anaesthetized, paralysed patients in a randomized crossover trial. The primary outcome was airway leak pressure. Secondary outcomes included time to insertion, the number of insertion and reposition attempts, leak volumes, and leak fractions. RESULTS: There was no significant difference between the airway leak pressures of the two devices [median (IQR) leak pressures 25 (22-30) vs 22 (20-28) cm H(2)O for the i-gel and LMA-U, respectively; P=0.083, 95% CI of the mean difference -0.32 to 4.88 cm H(2)O]. The median (IQR) insertion time for the i-gel was significantly less than for the LMA-U [12.2 (9.7-14.3) vs 15.2 (13.2-17.3) s; P=0.007]. All the LMA-U devices and 38 of 39 i-gel airways were inserted at the first attempt. The number of manipulations required after insertion to achieve a clear airway was the same in both the groups (four in each). There were no statistically significant differences in leak volumes or leak fractions during controlled ventilation. CONCLUSIONS: We found no difference in leak pressures and success rate of first-time insertion between the i-gel and the LMA-U. Time to successful insertion was significantly shorter for the i-gel. We conclude that the i-gel provides a reasonable alternative to the LMA-U for controlled ventilation during anaesthesia.

Comparison of the i-gel with the cuffed tracheal tube during pressure-controlled ventilation.

BACKGROUND: The i-gel (Intersurgical Ltd) is a novel device that differs from other supraglottic airway devices in that it has a softer and a non-inflatable cuff. Our study was designed to assess whether the i-gel is suitable to provide pressure-controlled ventilation (PCV) during anaesthesia by measuring the gas leaks and comparing these values with that of the tracheal tube. METHODS: Twenty-five patients, ASA I-II, were recruited to the study. Patients received a standard anaesthetic technique followed by an initial placement of the i-gel. The lungs were then ventilated at three different pressures (15, 20, 25 cm H(2)O) using PCV. The difference between the inspired and expired tidal volumes was used to calculate the leak volume. The leak fraction was defined as the leak volume divided by the inspired tidal volume. Following these observations, the i-gel was removed and replaced with the conventional tracheal tube and the recordings repeated. RESULTS: There was no significant difference between the leak fractions of the i-gel and the tracheal tube at 15 and 20 cm H(2)O PCV. At 25 cm H(2)O, the median difference in leak fraction was 0.02 (P=0.014) and the median difference in leak volume was 26.5 ml (P=0.006). There was no evidence of gastric insufflations with any of the pressures used during PCV. CONCLUSIONS: We suggest that the i-gel can be used as a reasonable alternative to tracheal tube during PCV with moderate airway pressures.

Apert syndrome and fetal hydrocephaly.

Apert (1906) was the first to identify a syndrome characterized by the association of acrocephaly with syndactyly, acrocephalosyndactylism. Since then Apert syndrome has been recognized as a clinical entity. Although hydrocephalus was rarely reported as an associated malformation, it was suggested that hydrocephalus might be responsible for mental retardation in some cases of Apert syndrome. We report a case of Apert syndrome presenting as fetal hydrocephaly at 28 weeks gestational age, and we review the literature. We suggest that hydrocephalus should be considered as a major associated malformation, and a complete evaluation with sonogram and computed tomography scan is recommended in any newborn suspected of having Apert syndrome after routine cephalometric measurement.