South African guidelines on the determination of death

Summary

Death is a medical occurrence that has social, legal, religious and cultural consequences requiring common clinical standards for its diagnosis and legal regulation. This document compiled by the Critical Care Society of Southern Africa outlines the core standards for determination of death in the hospital context. It aligns with the latest evidence-based research and international guidelines and is applicable to the South African context and legal system. The aim is to provide clear medical standards for healthcare providers to follow in the determination of death, thereby promoting safe practices and high-quality care through the use of uniform standards. Adherence to such guidelines will provide assurance to medical staff, patients, their families and the South African public that the determination of death is always undertaken with diligence, integrity, respect and compassion, and is in accordance with accepted medical standards and latest scientific evidence. The consensus guidelines were compiled using the AGREE II checklist with an 18-member expert panel participating in a three-round modified Delphi process. Checklists and advice sheets were created to assist with application of these guidelines in the clinical environment (https://criticalcare.org.za/resource/death-determination-checklists/).

Key points

Brain death and circulatory death are the accepted terms for defining death in the hospital context.

Death determination is a clinical diagnosis which can be made with complete certainty provided that all preconditions are met.

The determination of death in children is held to the same standard as in adults but cannot be diagnosed in children <36 weeks’ corrected gestation.

Brain-death testing while on extra-corporeal membrane oxygenation is outlined.

Recommendations are given on handling family requests for accommodation and on consideration of the potential for organ donation.

The use of a checklist combined with a rigorous testing process, comprehensive documentation and adequate counselling of the family are core tenets of death determination. This is a standard of practice to which all clinicians should adhere in end-of-life care.

South African guidelines on the determination of death

Death is a medical occurrence that has social, legal, religious and cultural consequences requiring common clinical standards for its diagnosis and legal regulation. This document compiled by the Critical Care Society of Southern Africa outlines the core standards for determination of death in the hospital context. It aligns with the latest evidence-based research and international guidelines and is applicable to the South African context and legal system. The aim is to provide clear medical standards for healthcare providers to follow in the determination of death, thereby promoting safe practices and high-quality care through the use of uniform standards. Adherence to such guidelines will provide assurance to medical staff, patients, their families and the South African public that the determination of death is always undertaken with diligence, integrity, respect and compassion, and is in accordance with accepted medical standards and latest scientific evidence. The consensus guidelines were compiled using the AGREE II checklist with an 18-member expert panel participating in a three-round modified Delphi process. Checklists and advice sheets were created to assist with application of these guidelines in the clinical environment (https://criticalcare.org.za/resource/death-determination-checklists/). Key points • Brain death and circulatory death are the accepted terms for defining death in the hospital context. • Death determination is a clinical diagnosis which can be made with complete certainty provided that all preconditions are met. • The determination of death in children is held to the same standard as in adults but cannot be diagnosed in children <36 weeks' corrected gestation. • Brain-death testing while on extra-corporeal membrane oxygenation is outlined. • Recommendations are given on handling family requests for accommodation and on consideration of the potential for organ donation. • The use of a checklist combined with a rigorous testing process, comprehensive documentation and adequate counselling of the family are core tenets of death determination. This is a standard of practice to which all clinicians should adhere in end-of-life care.

Real-time selected ion flow tube mass spectrometry to assess short- and long-term variability in oral and nasal breath

Breath-based non-invasive diagnostics have the potential to provide valuable information about a person's health status. However, they are not yet widely used in clinical practice due to multiple factors causing variability and the lack of standardized procedures. This study focuses on the comparison of oral and nasal breathing, and on the variability of volatile metabolites over the short and long term. Selected ion flow tube mass spectrometry (SIFT-MS) was used for online analysis of selected volatile metabolites in oral and nasal breath of 10 healthy individuals five times in one day (short-term) and six times spread over three weeks (long-term), resulting in nearly 100 breath samplings. Intra-class correlation coefficients (ICCs) were used to assess short- and long-term biological variability. Additionally, the composition of ambient air was analyzed at different samplings. The selected volatiles common in exhaled breath were propanol, 2,3-butanedione, acetaldehyde, acetone, ammonia, dimethyl sulfide, isoprene, pentane, and propanal. Additionally, environmental compounds benzene and styrene were analyzed as well. Volatile metabolite concentrations in ambient air were not correlated with those in exhaled breath and were significantly lower than in breath samples. All volatiles showed significant correlation between oral and nasal breath. Five were significantly higher in oral breath compared to nasal breath, while for acetone, propanal, dimethyl sulfide, and ammonia, concentrations were similar in both matrices. Variability depended on the volatile metabolite. Most physiologically relevant volatiles (acetone, isoprene, propanol, acetaldehyde) showed good to very good biological reproducibility (ICC > 0.61) mainly in oral breath and over a short-term period of one day. Both breathing routes showed relatively similar patterns; however, bigger differences were expected. Therefore, since sampling from the mouth is practically more easy, the latter might be preferred.

Airflow distribution with manual hyperinflation as assessed through gamma camera imaging: a crossover randomised trial

OBJECTIVES

Manual hyperinflation (MHI) has been shown to improve lung compliance, reduce airway resistance, and enhance secretion removal and peak expiratory flow. The aims of this study were to investigate whether there is a difference in airflow distribution through patients' lungs when using the Laerdal and Mapleson-C circuits at a set level of positive end-expiratory pressure (PEEP), and to establish whether differences in lung compliance and haemodynamic status exist when patients are treated with both these MHI circuits.

DESIGN

Crossover randomised controlled trial.

SETTING

Adult multidisciplinary intensive care unit (ICU) at an academic hospital.

PARTICIPANTS

Fifteen adult patients were recruited and served as their own controls.

INTERVENTION

In the Nuclear Medicine Department, MHI with PEEP 7.5 cmH(2)O was performed in the supine position (Day 1) with either Laerdal or Mapleson-C circuits, in a random order, while technetium-99m (Tc-99m) aerosol was administered and images were taken with a gamma camera. Changes in heart rate (HR), mean arterial pressure (MAP) and dynamic lung compliance (C(D)) were documented at baseline, immediately after return to ICU, and 10, 20 and 30 minutes after return to ICU. The alternative circuit was used on Day 2.

RESULTS

Tc-99m deposition was greater in the right lung field (62% and 63% for Laerdal and Mapleson-C circuits, respectively) than the left lung field (38% and 37%, respectively) for all patients, and least deposition occurred in the left lower segments (6% and 6%, respectively). No differences in Tc-99m deposition in the lungs, HR, MAP or C(D) were noted between the two MHI circuits.

CONCLUSION

Airflow distribution through patients' lungs was similar when the Laerdal and Mapleson-C MHI circuits were compared using a set level of PEEP in the supine position.

The Predictive Value of Diagnostic Sonography for the Effectiveness of Conservative Treatment of Tennis Elbow

OBJECTIVE

Tennis elbow is a common complaint. Several treatment strategies have been described, but an optimal strategy has not been identified. Sonographic imaging as a predictive factor has never been studied. The aim of our study was to determine the value of sonographic findings in predicting response to conservative therapy for tennis elbow. This was done in a randomized controlled trial in which the effectiveness of a brace only, physical therapy only, and a combination of both were compared.

SUBJECTS AND METHODS

Patients with tennis elbow complaints were randomized. Sonography was performed before randomization in 57 patients. Outcome measures at 6 weeks' follow-up were success rate and decrease in pain (scale, 0-100). Data were analyzed using an intention-to-treat analysis.

RESULTS

In only 75% of the imaged patients, sonographic abnormalities were identified and the clinical diagnosis could thus be confirmed. The following entities were identified: hypo- and hyperechogenicity, swelling, calcification, bursitis, enthesopathy, and tendinosis. The positive predictive value of sonography for the different entities varied between 0.78 and 0.82, and the negative predictive value ranged between 0.23 and 0.71. Predictive value was studied by subgroups of sonographic findings: hypoechoic, swelling present, enthesopathy, any entity present, and no entity present. We found no significant differences among the subgroups for either success rate (range, 40-54%) or mean decrease in pain (range, 16-28 percentage points).

CONCLUSION

No predictive value of sonography for the detection of abnormalities was identified in this study. Its diagnostic capability showed limited value. However, limitations in this study necessitate drawing definitive conclusions with care.

Activation of heterotrimeric G-protein signaling by a ras-related protein. Implications for signal integration

Utilizing a functional screen in the yeast Saccharomyces cerevisiae we identified mammalian proteins that activate heterotrimeric G-protein signaling pathways in a receptor-independent fashion. One of the identified activators, termed AGS1 (for activator of G-protein signaling), is a human Ras-related G-protein that defines a distinct subgroup of the Ras superfamily. Expression of AGS1 in yeast and in mammalian cells results in specific activation of Galpha(i)/Galpha(o) heterotrimeric signaling pathways. In addition, the in vivo and in vitro properties of AGS1 are consistent with it functioning as a direct guanine nucleotide exchange factor for Galpha(i)/Galpha(o). AGS1 thus presents a unique mechanism for signal integration via heterotrimeric G-protein signaling pathways.