Pyrethroid Poisoning.

INTRODUCTION: Pyrethroid compounds are widely used as insecticides. These compounds not only have a versatile application, but also have favourable toxicological profiles with high selectivity and toxicity to insects and low toxicity to humans. Despite this, there have been several reports of toxicity to humans in both occupational exposure and deliberate ingestional poisoning. CLASSICAL PRESENTATION AND TREATMENT: Two classical syndromic presentations are described. Type I syndrome is characterised predominantly by tremors and is seen with exposure to type I pyrethroids. Type II pyrethroids, which are structurally modified type I pyrethroids with the addition of a cyano group, can result in type II syndrome characterized by choreo-athetosis and salivation. Mega-dose poisoning and mixed poisoning, particularly with organophosphorus compounds, is associated with significant toxicity and death. Treatment is supportive and symptomatic. A favourable outcome can be expected in most patients. HOW TO CITE THIS ARTICLE: Ramchandra AM, Chacko B, Victor PJ. Pyrethroid Poisoning. Indian J Crit Care Med 2019;23(Suppl 4):S267-S271.

Cartap Hydrochloride Poisoning.

Cartap hydrochloride is a moderately hazardous nereistoxin insecticide that is increasingly used for deliberate self-harm in India. It can cause neuromuscular weakness resulting in respiratory failure. We report a patient with 4% Cartap hydrochloride poisoning who required mechanical ventilation for 36-hours. He recovered without any neurological deficits. We also review literature on Cartap hydrochloride poisoning.

Pharmacological interventions for preventing upper gastrointestinal bleeding in people admitted to intensive care units: a network meta-analysis.

OBJECTIVES: To assess the efficacy and safety of pharmacological interventions for preventing upper gastrointestinal (GI) bleeding in people admitted to intensive care units (ICUs). DESIGN AND SETTING: Systematic review and frequentist network meta-analysis using standard methodological procedures as recommended by Cochrane for screening of records, data extraction and analysis. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess the certainty of evidence. PARTICIPANTS: Randomised controlled trials involving patients admitted to ICUs for longer than 24 hours were included. SEARCH METHODS: The Cochrane Gut Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase and Latin American and Caribbean Health Science Information database (LILACS) databases were searched from August 2017 to March 2022. The search in MEDLINE was updated in April 2023. We also searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP). MAIN OUTCOME MEASURES: The primary outcome was the prevention of clinically important upper GI bleeding. RESULTS: We included 123 studies with 46 996 participants. Cimetidine (relative risk (RR) 0.56, 95% CI 0.40 to 0.77, moderate certainty), ranitidine (RR 0.54, 95% CI 0.38 to 0.76, moderate certainty), antacids (RR 0.48, 95% CI 0.33 to 0.68, moderate certainty), sucralfate (RR 0.54, 95% CI 0.39 to 0.75, moderate certainty) and a combination of ranitidine and antacids (RR 0.13, 95% CI 0.03 to 0.62, moderate certainty) are likely effective in preventing upper GI bleeding.The effect of any intervention on the prevention of nosocomial pneumonia, all-cause mortality in the ICU or the hospital, duration of the stay in the ICU, duration of intubation and (serious) adverse events remains unclear. CONCLUSIONS: Several interventions seem effective in preventing clinically important upper GI bleeding while there is limited evidence for other outcomes. Patient-relevant benefits and harms need to be assessed under consideration of the patients' underlying conditions.

Agreement between paired blood gas values in samples transported either by a pneumatic system or by human courier.

BACKGROUND: Rapid accurate assessment of metabolic derangements is crucial in the critically ill. We evaluated if arterial blood gas (ABG) samples transported through a pneumatic tube system (PTS) agreed with values transported by a human courier. METHODS: In this prospective study of 50-paired ABG samples, the couriered reference ABG was compared with those transported by PTS. Agreement was summarised by the mean difference with 95% limits of agreement (LOA) and Lin's concordance correlation (pc). RESULTS: The mean (±SD) time from sampling to analysis was 35.7±23.2 (courier) and 38.6±22.1 (PTS) minutes. Agreement was good between courier and PTS for pH, PaCO(2), bicarbonate, oxygen saturation and PaO(2) values (pc>0.97). Although the mean difference in PaO(2) values between PTS and courier was small (-0.9 mm Hg) and the agreement was good, individual differences were clinically significant (95% LOA -40.8 to 39.0). For PaO(2) <160 mm Hg, analysis of PTS samples yielded erroneously high PaO(2) values and vice versa for PaO(2)>160 mm Hg compared to manual courier. This suggested exaggerated oxygen movement between the blood sample and air in the PTS. CONCLUSIONS: In this study, analysis of samples transported through the PTS resulted in clinically unacceptable PaO(2) values. Delay in transport and analysis of ABG samples should be avoided and samples transported manually if they cannot be assessed on-site.

Genomic insights on heterogeneous resistance to vancomycin and teicoplanin in Methicillin-resistant Staphylococcus aureus: A first report from South India.

Methicillin-resistant Staphylococcus aureus (MRSA) infection is an important clinical concern in patients, and is often associated with significant disease burden and metastatic infections. There is an increasing evidence of heterogeneous vancomycin-intermediate S. aureus (hVISA) associated treatment failure. In this study, we aim to understand the molecular mechanism of teicoplanin resistant MRSA (TR-MRSA) and hVISA. A total of 482 MRSA isolates were investigated for these phenotypes. Of the tested isolates, 1% were identified as TR-MRSA, and 12% identified as hVISA. A highly diverse amino acid substitution was observed in tcaRAB, vraSR, and graSR genes in TR-MRSA and hVISA strains. Interestingly, 65% of hVISA strains had a D148Q mutation in the graR gene. However, none of the markers were reliable in differentiating hVISA from TR-MRSA. Significant pbp2 upregulation was noted in three TR-MRSA strains, which had teicoplanin MICs of 16 or 32 µg/ml, whilst significant pbp4 downregulation was not noted in these strains. In our study, multiple mutations were identified in the candidate genes, suggesting a complex evolutionary pathway involved in the development of TR-MRSA and hVISA strains.

The emergency physician's assessment of suicide risk in intentional self-poisoning using the modified SAD PERSONS scale versus standard psychiatric evaluation in a general hospital in South India: a cross-sectional study.

INTRODUCTION: The reliable identification, by emergency physicians, of those with intentional self-poisoning at risk of repeating attempts is crucial, particularly in countries with a shortfall of mental health professionals. METHODS: This cross-sectional study of intentional self-poisoning in India compared an emergency physician's assessment for the need for psychiatric referral, using the modified SAD PERSONS Scale (MSPS) as an interview guide, with a standard psychiatric interview. RESULTS: In 67 consecutive adults with intentional self-poisoning, MSPS cut-off scores of 5 or more best approximated psychiatric assessments for the need for psychiatric referral (positive likelihood ratio 2.9, 95% confidence interval [CI] 0.8-10.2; negative likelihood ratio 0.5, 95% CI 0.3-0.8). CONCLUSIONS: MSPS-guided emergency physicians' assessments after self-poisoning showed modest concordance with psychiatric assessments of suicide-risk. Concordance with psychiatric assessments may improve if risk factors prevalent in different settings are identified and incorporated in the MSPS.

Hypoglycemia - a rare complication of carbamazepine overdose.

Carbamazepine overdose usually presents with neurological manifestations such as ataxia, seizures and altered sensorium or cardiac manifestations that include tachycardia, hypotension and ventricular extra-systoles. We report a patient with carbamazepine overdose who manifested recurrent hypoglycemia on the third and fourth day following ingestion that resolved with supportive therapy.

Ecological economics and economic growth.

Boulding's 1966 paper on the economics of spaceship Earth established the framework for ecological economics and an understanding of economic growth. In ecological economics, economies are conceptualized as open subsystems of the closed biosphere and are subject to biophysical laws and constraints. Economic growth measured as an increase in real gross domestic product (GDP) has generally been associated with increases in the use of energy and materials and the generation of wastes. Scale, composition, and technology are the proximate determinants of environmental impacts. They are often reduced to two: scale (GDP) and intensity (impact per unit GDP). New work described in this paper defines "green" growth as intensity that declines faster than scale increases. Similarly, "brown" growth occurs when intensity declines more slowly than increases in scale, and "black" growth happens when both scale and intensity increase. These concepts are then related to the environmental Kuznets curve, which can be understood as a transition from brown to green growth. Ecological economics provides a macroperspective on economic growth. It offers broad policy principles, and it challenges the primacy of economic growth as a policy objective, but many important questions remain.