Errors and clinical supervision of intubation attempts by the inexperienced

Background: Tracheal intubation is an essential skill for anaesthetists and other disciplines that require emergency establishment of a secure airway. Early attempts in patients often meet with failure. Existing publications focus mainly on trainees in emergency settings and highlight the role of experience in success; most recommend prior simulation training. Common factors identified as contributing to difficulty have been difficult airways, emergencies and rapid sequence induction. Early intubation skill development in patients with anticipated straightforward airways in a controlled environment has received little attention. Objectives: This qualitative observational study aimed to identify common difficulties associated with a supervised intubation process by inexperienced personnel in the relatively stress-free conditions of elective surgical procedures in the operating theatre. Methods: Following institutional and ethical approval, participants, supervisors, anaesthetic assistants and patients consented to observation and video-recording of supervised intubations in a Durban teaching hospital. Anonymity and confidentiality were assured. Contemporaneous observations were recorded in theatre, and video-recordings were subsequently reviewed for content. Errors, and interactions between supervisor, assistant and participant, and associated outcomes, were identified. Results: Twenty participants (medical interns and medical, paramedical and nursing students) performing 72 intubations were observed. All participants had prior training using manikins or simulators. There were 61 successful intubations and 11 unsuccessful attempts. Factors associated with failure included unfamiliarity with airway, equipment or process. Process errors included inadequate head positioning, laryngoscope handling and tracheal tube manipulation. Anaesthetic assistants contributed to difficulties in some cases. Supervisor support was either verbal, physical or both. Less experienced supervisors tended to intervene earlier. There was a significant trend for success associated with the reported number of prior successful intubations. A successful intubation within the study was, however, no guarantee of subsequent success. Conclusion: Despite prior simulation training, many participants demonstrated lack of familiarity with the airway, intubation process and equipment. While improved simulation training might partly address these issues, supervision of early clinical intubation attempts needs to be redirected from the process of intubation itself to the process of intubation skills acquisition. A first step would be to ensure that all supervisors and assistants are trained for the latter goal, anticipating common errors and providing standardised conditions for success. The use of video-recording of the events is an invaluable aid to observation and interpretation, and is recommended as an adjunct to further studies of mechanical skills transfer

Identification of robust focus measure functions for the automated capturing of focused images from Ziehl-Neelsen stained sputum smear microscopy slide.

Capturing of the best-focused image using focus measure function (FMF) from a stack of images acquired at different focus distances is a crucial step in automatic microscopy development. Detection of bacilli present in Ziehl-Neelsen (ZN) stained sputum smears conventional microscope (CM) images is critical to disease diagnosis. Studies have revealed that the performances of FMFs are sensitive to image contents and background noise. In this article, 24 diverse FMFs were implemented on 31 stacks of CM's field of view images acquired from three different microscopes to determine the best-focused one. Seven FMFs achieved the accuracies of greater than 90%. Accuracy, focus error, and false maxima were calculated for each FMF, and overall score and ranking were also calculated for better interpretation. Preprocessing techniques such as filtering and image distortions (noise, contrast, saturation, illumination, etc.) were performed to evaluate the robustness of every FMF. Gaussian derivative, steerable filters, Tenengrad, and Hemli and Scherer's mean FMFs were identified as the most robust and accurate functions with the accuracy >90%. These FMFs have a relatively less focus error and false maxima rate. Full widths at half maximum of these four FMFs were also computed to determine their efficacy for the optimization process. These four FMFs can be implemented for automated capturing of the image from ZN-stained sputum smear slide. Gaussian derivative FMF can also be used effectively for both CM and fluorescence microscope's field of view image stacks to determine the best-focused one from each stack. © 2017 International Society for Advancement of Cytometry.

MMed cohort supervision: A path out of the swamp?

The authors present the case for collaborative cohort supervision (CCM), including both master's students and novice supervisors, as a possible way to rapidly increase the number of supervisors needed to address the recent implementation of a compulsory research component to specialist registration with the Health Professions Council of South Africa. Different models of CCM are discussed and possible pitfalls highlighted.

The research component of specialist registration--a question of alligators and swamps? A personal view.

The recent implementation of the research requirement for specialist registration presents difficulties with regard to the provision of research supervision, particularly in those medical schools that previously followed the path of qualification via the Colleges of Medicine of South Africa examinations. The differences between the requirements for research supervision as stated in the Health Professions Council of South Africa memorandum and those of the Committee for Higher Education are causing disparities between medical schools similar to those that led to the memorandum in the first place. While the research component of specialist training can only improve the quality of both patient care and academic endeavour, it requires an enormous investment of time on the part of both the specialist trainees and their supervisors. In order to deal with this, specific issues outlined in the article need to be addressed.

Municipal solid waste stabilisation by leachate recirculation.

The purpose of this study is to determine the impact of leachate recirculation on stabilisation of municipal solid wastes. The study was carried out by using two lab-scale landfill bioreactors containing approximately 10 kg of waste each, in order to follow waste degradation over 16 weeks of time period. The main difference between anaerobic recirculated and without recirculation bioreactors options is determined in leachate quality. Leachate quality is regularly measured by the means of pH, electrical conductivity, calcium, magnesium, total kjeldahl nitrogen, phosphate and chemical oxygen demand (COD). It has been observed that leachate recirculation is more effective on anaerobic degradation of solid waste than non-recirculated degradation. The leachate recirculated bioreactor appears to be the more effective option in the removal of COD by 89.93% and stabilisation of pH at 7.5. After 16 weeks of anaerobic degradation, waste stabilization seemed to have reached for the recirculated bioreactor. Therefore, further studies are required to determine the optimum operational conditions for leachate recirculation rates, also with the operational costs of recirculation for solid waste stabilisation.

'But it's just a spinal': combating increasing rates of maternal death related to spinal anaesthesia.

The number of women dying as a result of spinal anaesthesia during caesarean section in South Africa is steadily increasing in the triennial reports of the National Committee on Confidential Enquiry into Maternal Deaths (NCCEMD). This article postulates some of the reasons behind this phenomenon. The concern is raised that spinal anaesthesia is being undertaken inappropriately by poorly trained practitioners. A case is made for the rigorous application of known safety standards and for doctors to be appropriately trained in anaesthesia and to be solely responsible for the care of the mother during caesarean section. The need for doctors to be trained and prepared to administer general anaesthesia when required is noted.

First principles based design and experimental evidence for a ZnO-based ferromagnet at room temperature.

The introduction of ferromagnetic order in ZnO results in a transparent piezoelectric ferromagnet and further expands its already wide range of applications into the emerging field of spintronics. Through an analysis of density functional calculations we determine the nature of magnetic interactions for transition metals doped ZnO and develop a physical picture based on hybridization, superexchange, and double exchange that captures chemical trends. We identify a crucial role of defects in the observed weak and preparation sensitive ferromagnetism in ZnO:Mn and ZnO:Co. We predict and explain co-doping of Li and Zn interstitials to both yield ferromagnetism in ZnO:Co, in contrast with earlier insights, and verify it experimentally.

Prevention and treatment of cardiovascular instability during spinal anaesthesia for caesarean section.

Spinal anaesthesia is the method of choice for caesarean section. There is however a significant associated morbidity and mortality in South Africa, particularly in inexperienced hands. This review provides recommendations for safe practice for anaesthetists at all levels of expertise, with particular reference to the management of haemodynamic instability.

Anaesthesia for electroconvulsive therapy: a comparison of sevoflurane with propofol.

This study was a prospective audit of patients receiving either intravenous induction of anaesthesia with propofol 2 mg/kg or inhalational induction using 8% sevoflurane for patients undergoing electroconvulsive therapy (ECT). All patients received inhaled 50% nitrous oxide. The anaesthetic agent was determined by psychiatrist preference. Each psychiatrist nominated only one induction technique for all his or her patients. Seventy treatments were studied in each group. Induction time was longer in the sevoflurane group. The time from commencing induction to loss of verbal contact was [mean (SD)] 64 (29.9) seconds for sevoflurane and 36 (33.6) seconds for propofol (P=0.001). Time to loss of eyelash reflex was 82 (32.6)s for sevoflurane and 44 (17.9)s for propofol (P<0.001). The duration of seizure activity was longer in sevoflurane patients, 35 (17.8)s, compared with 20 (9.8)s in the propofol group (P< 0.001). Discharge times were similar Minor adverse effects occurred in three patients, all in the sevoflurane group (one bradycardia and two episodes of post-procedural nausea). There were no major adverse events in either group. Propofol and sevoflurane both appear to be suitable agents for induction of anaesthesia for ECT.

Acute spinal cord injury in pregnancy: an illustrative case and literature review.

Acute trauma is not all that uncommon in pregnancy. It accounts for 15% of non-obstetric maternal deaths. Moreover, about 15% of acute spinal cord injuries involve young women of childbearing age (Gilson et al., 1995). Most of the existing literature on spinal cord injury in pregnancy is concerned with the management of patients with pre-existing lesions; very few articles deal with acute injuries. We report the management of a case of acute spinal cord injury in the third trimester of pregnancy and review the major clinical issues associated with such cases.

Anaesthesia and analgesia for the critically ill parturient.

Anaesthetic and analgesic techniques in the critically ill are determined largely by the nature of the presenting illness. The commonest conditions likely to present as life-threatening emergencies are pre-eclampsia, obstetric haemorrhage, cardiac disease and severe sepsis. Issues dictating choice of anaesthetic technique are the patient's ability to maintain her airway, coagulation status, intravascular volume and haemodynamic dependence upon sympathetic drive, and requirements for ventilatory support and intensive care. Fetal well-being is an issue in the antepartum period, uteroplacental blood flow should be maintained and hypotension avoided. Maternal survival takes priority, however, and occasionally general anaesthetic techniques must be used which lead to neonatal respiratory depression and requirement for ventilatory support. Anaesthesia itself is associated with known hazards. The risks of each technique must be balanced against possible benefits in the context of the presenting illness.

Epidural compared with general anaesthesia for caesarean delivery in conscious women with eclampsia.

OBJECTIVE: To compare retrospectively the outcome of caesarean section under epidural anaesthesia with that of general anaesthesia in "stable" women with eclampsia. DESIGN: Retrospective review. METHOD: Over the five-year study period, there were 533 women with eclampsia and of these 66 women (12.4%), fulfilled the criteria of being 'stable'. Of the 66 women, 37 received epidural, 27 general, and 2 spinal anaesthesia. RESULTS: There were no major complications with either general or epidural anaesthesia. Epidural anaesthesia was associated with higher one-minute Apgar scores. CONCLUSION: This study indicates that both maternal and neonatal outcomes are not affected adversely by the use of epidural anaesthesia in selected cases of eclampsia.

Mivacurium for caesarean section in hypertensive parturients receiving magnesium sulphate therapy.

The interaction between mivacurium and magnesium sulphate was investigated in a group of parturients undergoing caesarean section under general anaesthesia. Thirty parturients were studied; 10 normotensive controls (group NT), 10 hypertensive controls (group HT) and 10 hypertensives who received magnesium sulphate (group HTM). At induction group HT received 30 microg/kg of alfentanil and group HTM 10 microg/kg of alfentanil and 30 or 60 mg/kg of magnesium sulphate. Neuromuscular function was monitored by electromyography. Mivacurium 0.15 mg/kg was given after 60% recovery of T1 following succinylcholine. Magnesium concentrations and plasma cholinesterase activity were significantly elevated in group HTM (1.57 +/- 0.53 mmol/1 and 4.60 +/- 1.27 kU/1) compared with group HT (0.71 +/- 0.18 mmol/1 and 3.44 +/- 0.97 kU/1) and group NT (0.60 +/- 0.07 mmol/1 and 2.86 +/- 0.82 kU/1) (P < 0.005). Time to maximal recovery, and time from 25-75% of maximal recovery from mivacurium, were significantly prolonged in group HTM (60.9 +/- 15.3 min and 16.8 +/- 5.6 min) compared with group HT (34.9 +/- 7.6 min and 7.6 +/- 3.6 min) and group NT (37.4 +/- 14.4 min and 8.5 +/- 3.4 min) (P < 0.01). Time to 25% recovery was prolonged in group HTM (35.1 +/- 7.4 min) compared with the other two groups (HT: 21.6 +/- 6.4 min and NT: 22.8 +/- 10.2 min) (P < 0.01). Whilst the duration of action of mivacurium, determined by electromyography, is prolonged by subtherapeutic serum magnesium concentrations, of the available non-depolarizing relaxants mivacurium would seem to be most appropriate for caesarean section.

A laboratory assessment of oxygen delivery from a portable chemical generator.

A simple portable chemical oxygen generator was tested in the laboratory. The device is designed for use by the public as an oxygen supply until an emergency team arrives with appropriate oxygen cylinders. The generator was found to supply a mean (SD) flow of oxygen of 3.6 (0.01) l.min-1 for 12.5 (range 12.4-12.6)min. The mean (SD) total volume of oxygen produced was 47(0.17) l. The supplied oxygen mask was a variable performance type with the problems and limitations inherent in this design; an oxygen flow of 8 l.min-1 is required to provide 40% oxygen and most of the oxygen is wasted and not available to the patient. This poses a serious limitation to any device which has a limited capability (in flow and/or total volume) for producing oxygen.

Use of a mechanical simulator for training in applying cricoid pressure.

Using an airway management training model, we have assessed anaesthesia personnel in their use of correct cricoid force and ability to retain this skill after a short training programme. A perspex device, working on a hydraulic principle, was used to measure cricoid pressure when applied to the model. After initial assessment at two levels of cricoid force (20 and 40 N), participants undertook additional training on 3 consecutive days. Thereafter, available participants underwent reassessment at 14-21 days. Forty-nine anaesthetic assistants and anaesthetists underwent initial assessment and 18 completed the full training and reassessment. Untrained, the majority (63%) of participants applied inadequate cricoid force with a wide variation (mean 16.8 (SD 9.3) (range 4.5-43.0) at 20 N and 32.9 (13.3) (14.9-74) at 40 N). After a single training session there was a marked improvement in application of cricoid force. Two additional training sessions did not provide further improvement. After 14-21 days the ability of participants to apply correct cricoid force was retained by 72% of subjects. Those who applied inadequate cricoid force initially were more likely to do so even after training. Most subjects applied too great a cricoid force in the first 5 s of application followed by a progressive loss of force during the next 20 s. This trend improved after training. We conclude that the majority of untrained personnel apply inadequate cricoid force, placing patients at risk of aspiration of gastric contents. While a simple training programme improved application of cricoid force, retained for up to 3 weeks, there was often a substantial decrease in the force applied to the cricoid during a single application, even after training.