The utility of point-of-care urinary lipoarabinomannan testing for the diagnosis of tuberculosis in critically ill patients: a prospective observational study.

BACKGROUND: Tuberculosis is a major global public health concern. Patients with tuberculosis who require critical care have a high mortality and delay in initiating antituberculous therapy is associated with increased mortality. Lipoarabinomannan (LAM) is a lipopolysaccharide found in the cell wall of Mycobacterium tuberculosis. Urinary LAM may be used as a bedside diagnostic test for tuberculosis. METHODS: The study was a single centre, prospective observational study that compared the utility of urinary LAM with conventional tuberculosis diagnostic modalities in patients with suspected tuberculosis who required intensive care admission. Urinary LAM testing was performed using the Alere Determine TB LAM Ag lateral flow assay test strips. A patient was classified as having confirmed tuberculosis if they met the following criteria: a clinical presentation compatible with tuberculosis, with either a positive TB culture, a positive GeneXpert, or a histological diagnosis of tuberculosis. RESULTS: Fifty patients were included in the study, with 12 having confirmed tuberculosis. All patients received mechanical ventilation, and the ICU mortality was 60%. Urinary LAM had a sensitivity of 50.0% (95% CI, 21.1 to 78.9%) and a specificity of 84.2% (95% CI, 68.8 to 94.0%) for confirmed tuberculosis. CONCLUSION: Urinary LAM allows for rapid bedside diagnosis of tuberculosis in critically ill patients. A positive urinary LAM should prompt consideration to initiate antituberculous treatment while the results of further diagnostic testing are awaited.

Hyperlactataemia with acute kidney injury following community assault: cause or effect?

BACKGROUND: Crush injury is a common presenting clinical problem in South African trauma patients, causing acute kidney injury (AKI). It has been theorised previously that the AKI was not due to an anaerobic phenomenon. A previous local study noted the presence of a mild hyperlactataemia among patients with crush syndrome, but the significance and causes of this was not fully explored. This study aimed to examine the incidence of hyperlactataemia in patients with crush syndrome presenting to a busy emergency department (ED) in rural South Africa. METHOD: The study was conducted at Edendale Hospital in KwaZulu-Natal province in South Africa from 1 June 2016 to 31 December 2017. All patients from the ED who had sustained a crush injury secondary to a mob assault were included in the study. Patients with GCS on arrival of < 13 or polytrauma were excluded from analysis. The primary outcome of interest was the presence of hyperlactataemia (> 2.0mmol/L) on presentation. The Kidney Disease Improving Global Outcomes (KDIGO) criteria were used to diagnose and stage AKI as a secondary outcome. RESULTS: A total of 84 patients were eligible for analysis. Sixty-nine (82%) patients presented with hyperlactataemia. The median serum lactate was 4.9mmol/L (IQR 2.3-7.2mmol/L). Fifteen (18%) patients were diagnosed with AKI on presentation according to serum creatinine. Ten patients were diagnosed as Stage 1, three were Stage 2 and two Stage 3 AKI respectively. There was no difference in the incidence of AKI in patients with or without hyperlactataemia (p = 0.428). Time from injury to presentation was a median 365 minutes (IQR 180-750 minutes). Six (7%) patients were admitted to high care unit and nine (11%) were admitted to the intensive care unit (ICU). No patients died within 48 hours of admission. Two patients received renal replacement therapy during the first 48 hours of admission to hospital. CONCLUSION: Hyperlactataemia is a common feature of patients presenting to the ED following crush syndrome secondary to beatings received during interpersonal violence. The origin of this hyperlactataemia is currently unknown. Further research needs to be conducted into the origin of the hyperlactataemia and its clinical significance. In this cohort, the utilisation of RRT was low but the incidence of AKI was high and developed rapidly following the injury. The utilisation of RRT also needs to be further studied in larger patient populations in South Africa to make local clinical recommendations for use.

Acute Kidney Injury on Presentation to a Major Trauma Service is Associated with Poor Outcomes.

BACKGROUND: This study sought to describe the burden of disease of acute kidney injury (AKI) among adult South African trauma patients who presented to a tertiary level trauma service. METHODS: The trauma database was interrogated for the period from December 2012 to July 2017. All patients over the age of 18 y, who were admitted following trauma, were included. Outcome data were reviewed. This included in-hospital mortality, need for intensive care unit admission, and length of stay. AKI was defined according to the latest Kidney Disease Improving Global Outcomes guidelines using the presentation serum creatinine. RESULTS: A total of 7613 patients were admitted for trauma over the period under review. Four thousand two hundred sixty-six patients were suitable for analysis. A total of 238 (5.6%) patients presented with AKI, 149 (62.6%) had stage 1 AKI, 40 (16.8%) had stage 2 AKI, and 49 (20.6%) had stage 3 AKI. There was a higher incidence of AKI in patients with blunt trauma. The length of stay, need for intensive care unit admission, and mortality were significantly higher in patients presenting with AKI than in those who did not present with AKI. There were 172 deaths (4.0%). The patients who died were older and had significantly higher Injury Severity Score than survivors. They were more acidotic on presentation, had lower Glasgow Coma Scale, and were more likely to be hypotensive on presentation. They also were significantly more likely to have AKI on presentation. (30.2% versus 5.6% P < 0.001). AKI on presentation was an independent risk factor for mortality (odds ratio 3.038 95% confidence interval 1.260-7.325). CONCLUSIONS: AKI is common in patients presenting to our center with acute trauma. The presence of AKI is associated with increased morbidity and mortality. Efforts must be directed to improving recognition of at-risk patients. Prompt referral and adequate resuscitation of trauma patients before transfer must be prioritized.

Hyperchloraemia is associated with acute kidney injury and mortality in the critically ill: A retrospective observational study in a multidisciplinary intensive care unit.

PURPOSE: The aim of this study was to determine whether serum chloride and changes in serum chloride over time were associated with acute kidney injury (AKI) or intensive care unit (ICU) mortality in a heterogenous critically ill population. MATERIALS AND METHODS: The study was a retrospective observational study of 250 adult patients admitted to a multidisciplinary academic ICU. Serum chloride within 48 h of admission, changes in chloride, and other biochemical and clinical parameters were evaluated as predictors of AKI and mortality. RESULTS: Hyperchloraemia occurred in 143 (57.2%) patients within 48 h of ICU admission. Hyperchloraemia at 48 h was significantly associated with AKI, OR = 6.44 (95% CI 2.95-14.10) and mortality, OR = 2.46 (95% CI 1.22-4.94) on univariate analysis, with this association persisting on multivariable analysis. An increase in serum chloride was also associated with a significantly increased risk of AKI and mortality on univariate analysis. Hyperchloraemia on admission was, however, not associated with AKI or death. Of the 150 patients with AKI, 147 (98.0%) had developed AKI by 48 h. CONCLUSIONS: Hyperchloraemia and increasing serum chloride are associated with adverse outcomes in critically ill patients. There is equipoise as to whether this represents an association, an epiphenomenon or causation.

Serum procalcitonin levels predict acute kidney injury in critically ill patients.

AIM: To determine whether admission procalcitonin (PCT) was associated with the subsequent development of acute kidney injury (AKI) in a general population of critically ill patients. METHODS: The study was a retrospective observational study conducted in a multidisciplinary intensive care unit (ICU) over a period of 1 year. Adult patients who had a PCT performed on admission and who did not have chronic kidney disease (CKD) or AKI on admission, were evaluated for the development of AKI within the first week of ICU admission, according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria. The association between PCT on admission and the development of AKI was explored for the entire cohort and for septic and non-septic subgroups. RESULTS: Two hundred and one patients were included in the study. The incidence of AKI in the first 7 days of ICU admission was 36.8%. PCT, age, the presence of shock on admission, and sepsis were significantly associated with AKI on univariate analysis. Multivariable analysis of the entire cohort revealed that age, shock and sepsis remained independent predictors of AKI, while PCT was no longer significant. When the septic and non-septic patients were analyzed separately a PCT ≥10 ng/mL remained the only significant predictor of AKI in the non-septic patients (OR 4.430; 95% CI 1.464-13.399), but was not an independent predictor of AKI in septic patients. CONCLUSION: The main finding of this study was the significant association of an elevated PCT on admission with the development of AKI in the non-septic patient. An elevated PCT in a non-septic patient identifies a patient at increased risk of AKI. PCT requires further study as a novel biomarker of AKI in non-septic patients.

Critical care admission of South African (SA) surgical patients: Results of the SA Surgical Outcomes Study.

BACKGROUND: Appropriate critical care admissions are an important component of surgical care. However, there are few data describing postoperative critical care admission in resource-limited low- and middle-income countries. OBJECTIVE: To describe the demographics, organ failures, organ support and outcomes of non-cardiac surgical patients admitted to critical care units in South Africa (SA). METHODS: The SA Surgical Outcomes Study (SASOS) was a 7-day national, multicentre, prospective, observational cohort study of all patients ≥16 years of age undergoing inpatient non-cardiac surgery between 19 and 26 May 2014 at 50 government-funded hospitals. All patients admitted to critical care units during this study were included for analysis. RESULTS: Of the 3 927 SASOS patients, 255 (6.5%) were admitted to critical care units; of these admissions, 144 (56.5%) were planned, and 111 (43.5%) unplanned. The incidence of confirmed or strongly suspected infection at the time of admission was 35.4%, with a significantly higher incidence in unplanned admissions (49.1 v. 24.8%, p<0.001). Unplanned admission cases were more frequently hypovolaemic, had septic shock, and required significantly more inotropic, ventilatory and renal support in the first 48 hours after admission. Overall mortality was 22.4%, with unplanned admissions having a significantly longer critical care length of stay and overall mortality (33.3 v. 13.9%, p<0.001). CONCLUSION: The outcome of patients admitted to public sector critical care units in SA is strongly associated with unplanned admissions. Adequate 'high care-dependency units' for postoperative care of elective surgical patients could potentially decrease the burden on critical care resources in SA by 23%. This study was registered on ClinicalTrials.gov (NCT02141867).

Hypoxaemia on arrival in a multidisciplinary intensive care unit.

BACKGROUND: Transport of the critically ill patient poses the risk of numerous complications. Hypoxaemia is one such serious adverse event and is associated with potential morbidity and mortality. It is, however, potentially preventable. OBJECTIVE: To determine the incidence of hypoxaemia on arrival in a tertiary multidisciplinary intensive care unit (ICU) and to identify risk factors for this complication. METHOD: A retrospective observational study was conducted at King Edward VIII Hospital, Durban, South Africa, from May 2013 to February 2014. RESULTS: Hypoxaemia occurred in 15.5% of admissions sampled. Statistically significant risk factors for hypoxaemia on univariate analysis (p<0.05) included lack of peripheral capillary oxygen saturation (SpO2) monitoring, transfer by an intern as opposed to other medical/paramedical staff, and transfer from internal medicine. Use of neuromuscular blockers and transfer from theatre were protective. Binary logistic regression analysis revealed lack of SpO2 monitoring to be the only significant independent predictor of hypoxaemia (odds ratio 6.1; 95% confidence interval 1.5 - 24.5; p=0.02). CONCLUSION: Hypoxaemia is common on admission to the ICU and may be prevented by simple interventions such as appropriate transport monitoring.