The ASOS Surgical Risk Calculator: development and validation of a tool for identifying African surgical patients at risk of severe postoperative complications

BACKGROUND

The African Surgical Outcomes Study (ASOS) showed that surgical patients in Africa have a mortality twice the global average. Existing risk assessment tools are not valid for use in this population because the pattern of risk for poor outcomes differs from high-income countries. The objective of this study was to derive and validate a simple, preoperative risk stratification tool to identify African surgical patients at risk for in-hospital postoperative mortality and severe complications.

METHODS

ASOS was a 7-day prospective cohort study of adult patients undergoing surgery in Africa. The ASOS Surgical Risk Calculator was constructed with a multivariable logistic regression model for the outcome of in-hospital mortality and severe postoperative complications. The following preoperative risk factors were entered into the model; age, sex, smoking status, ASA physical status, preoperative chronic comorbid conditions, indication for surgery, urgency, severity, and type of surgery.

RESULTS

The model was derived from 8799 patients from 168 African hospitals. The composite outcome of severe postoperative complications and death occurred in 423/8799 (4.8%) patients. The ASOS Surgical Risk Calculator includes the following risk factors: age, ASA physical status, indication for surgery, urgency, severity, and type of surgery. The model showed good discrimination with an area under the receiver operating characteristic curve of 0.805 and good calibration with c-statistic corrected for optimism of 0.784.

CONCLUSIONS

This simple preoperative risk calculator could be used to identify high-risk surgical patients in African hospitals and facilitate increased postoperative surveillance.

CLINICAL TRIAL REGISTRATION

NCT03044899.

Strategies to improve the performance of learners in a nursing college. Part I: Issues pertaining to nursing education

The aim of this contextual, exploratory, descriptive and qualitative study was to describe strategies to improve the performance of learners in a nursing college. The article seeks to deal with factors relating to nursing education that contribute to the poor performance of learners and to outline related strategies to improve the situation. Three focus group interviews were conducted. One group was formed by seven tutors, and the other two groups were formed by fourth-year learners following a four-year comprehensive diploma course. All participants voluntarily took part in the study. Data was analyzed using the descriptive method of open coding by Tesch (in Creswell, 1994:154-156). Trustworthiness was ensured in accordance with Lincoln and Guba's (1985:290-326) principles of credibility, conformability, transferability and dependability. The findings were categorized into issues pertaining to nursing education as follows: curriculum overload; lack of theory and practice integration; teaching and assessment methods that do not promote critical thinking; tutors' lack of skills and experience; inadequate preparation of tutors for lectures; insufficient knowledge of tutors regarding outcomes-based education approach to teaching and learning; inadequate process of remedial teaching; discrepancies between tutors' marking; lack of clinical role-models and high expectations from the affiliated university as regards standards of nursing development programme by the staff development committee of the nursing college under study for implementation. Future research should focus on the effectiveness of the described strategies to improve the learners' performance. It is also recommended that similar studies be conducted or replicated in other nursing colleges to address the problem of poor performance of learners engaged in a four-year comprehensive diploma course.

Strategies to improve the performance of learners in a nursing college. Part II: Issues pertaining to management, attitudes and values

This article forms part two of a bigger study that was conducted in a nursing college to explore and describe the reasons for the poor performance of learners. Part one of the study dealt with the issues pertaining to education, while this article (part two) seeks to describe issues pertaining to management, attitudes and values that lead to the poor performance of learners in the nursing college under study. A qualitative, exploratory and descriptive design that was contextual in nature was employed, and three focus groups interviews were conducted. Seven tutors formed one group while other two groups were formed by fourth-year learners following a comprehensive diploma course. All participants voluntarily participated in the study. Data was analyzed using the descriptive method of open coding in accordance with Tesch's protocol (in Creswell, 1994:154-156). Trustworthiness was ensured using the following principles: credibility, conformability, transferability and dependability (Lincoln & Guba 1985:290-326). Findings were categorized into issues pertaining to management, attitudes and values that had an influence on the poor performance of learners as follows:

MANAGEMENT

Inadequate resources and study facilities; policies that change frequently; tutors' dissatisfaction with regard to staff development, the lack of involvement by management and lack of management support, staff shortage and maldistribution of staff members; ineffective selection process of learners; inconsistent regulations, and too many of them; policies and procedures resulting in confusion and poor discipline. Attitudes and values: Tutors' lack of motivation and interest, lack of respect by learners and no team work among tutors. Through a conceptualization process and the recommendations by participants, strategies to improve the learners' performance were described. It is recommended that these strategies be submitted to the staff development committee for implementation and future follow-up research be undertaken to determine the effectiveness of the strategies. It is also recommended that other nursing colleges replicate the study within their context.

Calcium alginate entrapment of the yeast Rhodosporidium toruloides for the kinetic resolution of 1,2-epoxyoctane

Resting cells of the yeast Rhodosporidium toruloides (UOFS Y-0471) were immobilised in calcium alginate beads for the enantioselective kinetic resolution of racemic-1,2-epoxyoctane. The initial activity exhibited by immobilised cells was almost 50% lower than that of the free counterpart but was extremely stable when compared to the free cells. The concentration of the immobilised biomass had no effect on apparent enzyme activity but did lead to a decrease in single cell activity. An increase in both the alginate and CaCl2 concentrations used for bead preparation led to a decrease in enzyme stability. An increase in the alginate concentration led to an increase in bead diameter. The stoichiometric equation for cross-linking of alginate was only obeyed when CaCl2 concentrations higher than 0.4 M were utilised for bead preparation.

Early bactericidal activity of amoxicillin in combination with clavulanic acid in patients with sputum smear-positive pulmonary tuberculosis

The early bactericidal activity (EBA) of an antituberculosis agent is the rate of decrease in viable colony-forming units (CFU) per milliliter of sputum during the first 2 d of treatment of patients with previously untreated smear-positive pulmonary tuberculosis. The objective of this open randomized study was to evaluate the EBA of the combination of amoxicillin 3 g and clavulanic acid 750 mg. Ten patients with a mean age of 34 y and a mean weight of 56 kg received amoxicillin/clavulanic acid and 5 patients with a mean age of 34 y and a mean weight of 57 kg received no drug. In the patients receiving 1 dose of amoxicillin/clavulanic acid daily for 2 d the mean log10CFU/ml of sputum before treatment was 6.7402 (SD 0.539) and after 2 d of treatment 6.7046 (SD 0.609); the corresponding values in patients receiving no drug were 6.7823 (SD 0.563) and 6.7502 (SD 0.673), respectively. The EBA of 0.018 (SD 0.130) in patients receiving amoxicillin/clavulanic acid did not differ significantly from that of 0.016 (SD 0.069) in patients receiving no drug. It is unlikely that the combination of amoxicillin/clavulanic acid has an important place in the treatment of tuberculosis with the exception of those patients with multidrug-resistant tuberculosis who are otherwise therapeutically destitute.

Chloroquine administration in mice increases beta-amyloid immunoreactivity and attenuates kainate-induced blood-brain barrier dysfunction

The anti-malarial drug chloroquine (CHL) has been reported to cause the accumulation of beta-amyloid peptide containing fragments (fA beta) of the amyloid precursor protein within lysosomes in vitro. However, the significance of this finding with regards to the development of Alzheimer's disease (AD) pathology in vivo is not known. Hence, we investigated the effects of chronic CHL administration in the mouse. Systemically administered CHL caused an astrocytic response and an increase in intracellular A beta immunoreactivity throughout the brain, but no plaque-like pathology. Pharmacological challenge with the excitotoxin kainic acid (KA) revealed a mild proconvulsant effect of CHL pretreatment (P < 0.06). Interestingly, CHL protected the blood-brain barrier from characteristic KA-induced dysfunction. Given the hypothesized involvement of both excitotoxic processes and the vascular system in AD, the observed interactions may assist in elucidating the pathogenesis of AD.

Buerger's disease. A case report and review of the literature

A case of thrombo-angiitis obliterans (Buerger's disease) in a 30-year-old man is reported. Irremediable gangrene necessitated amputation of both legs, and distal amputation of the fingers and thumb of the right hand.

Ruptured abdominal aortic aneurysm associated with an aorto-enteric fistula. A case report

A patient with a ruptured abdominal aortic aneurysm and a primary aortoduodenal fistula is reported on. Treatment included aneurysmectomy, suture of the duodenal fistula, closure of the proximal and distal abdominal aortic stumps, and construction of an axillobifemoral bypass. The postoperative course was complicated by spinal cord ischaemia and pataplegia, Gram-negative septicaemia, secondary intra-abdominal haemorrhage and multiple abscess formation.

Rectus sheath haematoma--a complication of anticoagulation therapy. A case report

A right-sided rectus sheath haematoma developed during heparin therapy for deep vein thrombosis. Computed tomography of the abdomen provided accurate pre-operative images of the size and extent of the haematoma, and surgical evacuation thereof resulted in uneventful recovery.