A cross-sectional observational study of endotracheal intubation and extubation practices among doctors treating adult COVID-19 and suspected COVID-19 patients in South Africa.

BACKGROUND: Patients with severe COVID-19 may require endotracheal intubation. Unique adjustments to endotracheal intubation and extubation practices are necessary to decrease the risk of SARS-CoV-2 transmission to healthcare workers (HCWs) while avoiding complications of airway management. OBJECTIVES: To investigate the practice of endotracheal intubation and extubation, resources available and complications encountered by clinicians performing endotracheal intubation and extubation of COVID-19 and suspected COVID-19 patients in South Africa (SA). METHOD: A cross-sectional observational study was conducted during the initial surge of COVID-19 cases in SA. Data were collected by means of a self-administered questionnaire completed by clinicians in the private and public healthcare sectors after performing an endotracheal intubation and/or extubation of a patient with confirmed or suspected COVID-19. RESULTS: Data from 135 endotracheal intubations and 45 extubations were collected. Anaesthetists accounted for 87.0% (n=120) of the study participants, specialist clinicians in their respective fields for 59.4% (n=82), and public HCWs for 71.0% (n=98). Cases from Gauteng Province made up 76.8% (n=106) of the database. Haemoglobin desaturation was the most frequent complication encountered during endotracheal intubation (40.0%; n=54). Endotracheal intubations performed at private healthcare institutions were associated with a significantly lower complication rate of 17.5% (n=7) compared with 52.6% (n=50) in the public healthcare sector (p<0.001). Endotracheal intubations performed in theatre had the lowest complication rate of 10.4% (n=5; p<0.001). Propofol was used in 90 endotracheal intubations (66.7%), and its use was associated with fewer complications relative to other induction agents. Minimising the number of intubation attempts (p=0.009) and the use of checklists (p=0.013) significantly reduced the frequency of complications encountered during endotracheal intubation. Intravenous induction technique, neuromuscular blocking agent used, intubating device used and time at which intubation was performed did not affect the incidence of complications. The majority of endotracheal extubations were uncomplicated (88.9%). CONCLUSIONS: The study provides valuable insight into the resources used by clinicians and complications encountered when endotracheal intubations and/or extubations were performed. Data from this study may be used to guide future clinical practice and research, especially in resource-limited settings.

SARS-CoV-2 infection prevalence in healthcare workers and administrative and support staff: The first-wave experience at three academic hospitals in the Tshwane district of Gauteng Province, South Africa.

BACKGROUND: The availability of well and functional healthcare workers (HCWs) and support staff is pivotal to a country's ability to manage the COVID-19 pandemic effectively. While HCWs have been identified as being at increased risk for acquisition of SARS-CoV-2 infection, there is a paucity of data pertaining to South African (SA) HCW-related infection rates. Global and provincial disparities in these numbers necessitate local data in order to mitigate risks. OBJECTIVES: To ascertain the overall SARS-CoV-2 infection rates and outcomes among all hospital staff at three hospitals in the Tshwane district of Gauteng Province, SA, and further determine associations with the development of severe COVID-19 disease. METHODS: This retrospective audit was conducted across three academic hospitals in the Tshwane district for the period 1 June - 31 August 2020. Deidentified data from occupational health and safety departments at each hospital were used to calculate infection rates. A more detailed analysis at one of the three hospitals included evaluation of demographics, work description, possible source of SARS-CoV-2 exposure (community or hospital), comorbidities and outcomes. RESULTS: The period prevalence of SARS-CoV-2 infections ranged from 6.1% to 15.4% between the three hospitals, with the average period prevalence being 11.1%. The highest incidence of SARS-CoV-2 infections was observed among administrative staff (2.8 cases per 1 000 staff days), followed by nursing staff (2.7 cases per 1 000 staff days). Medical doctors had the lowest incidence of 1.1 cases per 1 000 staff days. SARS-CoV-2 infections were categorised as either possibly community or possibly healthcare facility acquired for 26.6% and 73.4% of the infections, respectively. The administrative group had the highest proportion of possible community-acquired infections (41.8%), while doctors had the lowest (6.1%). The mean age of individuals with mild and severe disease was 41 years and 46.1 years, respectively (p=0.004). The presence of comorbidities was significantly associated with severity of disease (p=0.002). CONCLUSIONS: This study highlights that hospital staff, including administrative staff, are clearly at high risk for acquisition of SARS-CoV-2 infection during a surge.

Modelling Representative Population Mobility for COVID-19 Spatial Transmission in South Africa.

The COVID-19 pandemic starting in the first half of 2020 has changed the lives of everyone across the world. Reduced mobility was essential due to it being the largest impact possible against the spread of the little understood SARS-CoV-2 virus. To understand the spread, a comprehension of human mobility patterns is needed. The use of mobility data in modelling is thus essential to capture the intrinsic spread through the population. It is necessary to determine to what extent mobility data sources convey the same message of mobility within a region. This paper compares different mobility data sources by constructing spatial weight matrices at a variety of spatial resolutions and further compares the results through hierarchical clustering. We consider four methods for constructing spatial weight matrices representing mobility between spatial units, taking into account distance between spatial units as well as spatial covariates. This provides insight for the user into which data provides what type of information and in what situations a particular data source is most useful.

Fasting plasma glucose and risk factor assessment: Comparing sensitivity and specificity in identifying gestational diabetes in urban black African women.

BACKGROUND: Identifying women with gestational diabetes mellitus (GDM) allows interventions to improve perinatal outcomes. A fasting plasma glucose (FPG) level ≥5.1 mmol/L is 100% specific for a diagnosis of GDM. The International Association of Diabetes and Pregnancy Study Groups acknowledges that FPG <4.5 mmol/L is associated with a low probability of GDM. OBJECTIVES: The validity of selective screening based on the presence of risk factors was compared with the universal application of FPG ≥4.5 mmol/L to identify women with GDM. FPG ≥4.5 mmol/L or the presence of one or more risk factors was assumed to indicate an intermediate to high risk of GDM and therefore the need for an oral glucose tolerance test (OGTT). METHODS: Consecutive black South African (SA) women were recruited to a 2-hour 75 g OGTT at 24 - 28 weeks' gestation in an urban community health clinic. Of 969 women recruited, 666 underwent an OGTT, and of these 589 were eligible for analysis. The glucose oxidase laboratory method was used to measure plasma glucose concentrations. The World Health Organization GDM diagnostic criteria were applied. All participants underwent a risk factor assessment. The χ2 test was used to determine associations between risk factors and a positive diagnosis of GDM. The sensitivity and specificity of a positive diagnosis of GDM were calculated for FPG ≥4.5 mmol/L, FPG ≥5.1 mmol/L, and the presence of one or more risk factors. RESULTS: The prevalence of overt diabetes mellitus and GDM was 0.5% and 7.0%, respectively. Risk factor-based selective screening indicated that 204/589 (34.6%) of participants needed an OGTT, but 18/41 (43.9%) of positive GDM diagnoses were missed. Universal screening using the FPG threshold of ≥4.5 mmol/L indicated that 152/589 (25.8%) of participants needed an OGTT, and 1/41 (2.4%) of positive diagnoses were missed. An FPG of ≥5.1 mmol/L identified 36/41 (87.8%) of GDM-positive participants. The sensitivity and specificity of the presence of one or more risk factors were 56% and 67%, respectively. The sensitivity and specificity of FPG ≥4.5 mmol/L were 98% and 80%, respectively. CONCLUSIONS: Universal screening using FPG ≥4.5 mmol/L had greater sensitivity and specificity in identifying GDM-affected women and required fewer women to undergo a resource-intensive diagnostic OGTT than risk factor-based selective screening. A universal screening strategy using FPG ≥4.5 mmol/L may be more efficient and cost-effective than risk factor-based selective screening for GDM in black SA women.

Low molecular weight quaternised chitosan (11): in vitro assessment of absorption enhancing properties.

N-Trimethyl chitosan chloride (TMC; high molecular weight) and N-trimethyl chitosan oligosaccharide (TMO; low molecular weight) with different degrees of quaternisation were synthesised and evaluated for their absorption enhancing properties across mucosal epithelia. These quaternised chitosan derivatives (0.0625% w/v-0.5% w/v) showed a significant decrease in the transepithelial electrical resistance (TEER) of cultured rabbit tracheal epithelial cell monolayers as compared to the control. The degree of quaternisation and concentration of the compounds influenced the extent of the reduction in TEER. Higher degrees of quaternisation and an increase in the concentration of the compound were associated with a more pronounced reduction in the TEER. The TMO derivatives seemed to be more effective in lowering the TEER of tracheal cell monolayers as compared to the TMC polymers. Ciliary beat frequency (CBF) is the main defence mechanism of the respiratory tract and is therefore a useful parameter in evaluating the toxicity of nasally administered drugs and additives. The effect of the synthesised chitosan derivatives on the CBF of human nasal epithelial cells at pH 7.4 was determined by a method based on an analogue contrast enhancement technique. The TMO oligomers exhibited lower inhibition of the CBF of human nasal epithelial cells compared to that of the TMC polymers. It was proposed that this reduced effect on the CBF is due to the lower viscosity and molecular weight of TMO. However, no acute toxicity was found with any of the synthesised chitosan derivatives by means of the CBF tests conducted in this study.