ObjectivesForest fires in South Asia lead to widespread haze, where many healthy individuals develop psychosomatic symptoms. We investigated the effects of haze exposure on cerebral hemodynamics and new symptoms. We hypothesised that vasoactive substances present in the haze, would lead to vasodilation of cerebral vasculature, thereby altering cerebral hemodynamics, which in turn may account for new psychosomatic symptoms.MethodsSeventy-four healthy volunteers were recruited, and serial transcranial Doppler (TCD) ultrasonography was performed to record blood flow parameters of bilateral middle cerebral arteries (MCA). The first TCD was performed in an air-conditioned environment. It was repeated outdoors after the participants spent 30-minutes in the haze environment. The prevailing level of pollutant standards index (PSI) was recorded. Appropriate statistical analyses were performed to compare cerebral hemodynamics at baseline and after haze exposure in all participants. Subgroup analyses were then employed to compare the findings between symptomatic and asymptomatic participants.ResultsStudy participants’ median age was 30 years (IQR 26–34), and new psychosomatic symptoms were reported by 35 (47.3%). There was a modest but significant decrease in pulsatility index (PI) and resistivity index (RI) in the left MCA after haze exposure (PI: p = 0.026; RI: p = 0.021). When compared to baseline parameters, haze exposure resulted in significantly lower mean PI (p = 0.001) and RI (p = 0.001) in symptomatic patients, but this difference was not present in asymptomatic patients (PI: p = 0.919; RI: p = 0.970).ConclusionHaze causes significant alterations in cerebral hemodynamics in susceptible individuals, probably responsible for various psychosomatic symptoms. The prognostic implications and health effects of haze require evaluation in a larger study.

Background and Rationale:Uncertainty persists over the optimal management of blood pressure (BP) in the early phase of acute ischemic stroke (AIS). This study aims to determine the safety and effects of intensive BP lowering on cerebral blood flow (CBF) and functional in AIS patients treated with intravenous thrombolysis.Methods:In a randomized controlled trial, 54 thrombolysed AIS patients with a systolic BP of 160 to 180 mm Hg will be randomized to early intensive BP lowering (systolic target range 140–160 mm Hg) or guideline-based BP management (systolic range 160–180 mm Hg) during first 72-hours using primarily intravenous labetalol. We hypothesize that early intensive BP lowering will not reduce CBF by 20% and/or increase the volume of hypoperfused tissue by >20% on computed tomographic perfusion. Clinical outcome will be assessed using a dichotomized modified Rankin scale (scores 0–1 as excellent outcome vs scores 2–6 as dead or dependent) at 90 days. Other outcome would be symptomatic intracerebral hemorrhage. The trial is registered at ClinicalTrials.gov, NCT03443596.Conclusion:This randomized study will provide important information about the physiological effects of BP reduction on cerebral perfusion after intravenous thrombolysis in AIS.

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Introduction: Uncertainty persists over the optimal management of blood pressure (BP) in the early phase of acute ischemic stroke (AIS). This study aims to determine the safety and effects of intensive BP lowering on cerebral blood flow and functional outcomes in AIS patients treated with intravenous thrombolysis. Methods: In a randomized controlled trial, AIS patients with a systolic BP of 160-180mmHg were randomized to early intensive BP lowering (systolic target range 140-160mmHg) or guideline-based BP management (systolic range 160-180mmHg) during first 72-hours using primarily intravenous labetalol. All study subjects underwent CT perfusion at baseline, 24 and 72-hours post-randomization to evaluate change in cerebral hemodynamics. Clinical outcome was assessed using a dichotomized modified Rankin scale (scores 0-1 as excellent outcome versus scores 2-6 as poor outcome) at 90 days. Results: Of the 48 recruited patients, 25 (52%) were assigned to the early intensive BP lowering arm and 23 (48%) to the guideline-based BP management arm. Excellent functional outcome at 90 days were similar in the 2 arms- 56% in the early intensive BP lowering arm and 61% in the standard therapy arm. There were no significant differences in the baseline, 24 and 72-hour CT perfusion cerebral hemodynamic parameters or symptomatic intracranial hemorrhage between the 2 study arms. Conclusions: In the early phase of AIS, intensive BP lowering appears to be a safe strategy. Large randomized controlled trials are needed to confirm our study findings.

Background: Bleeding of the gastrointestinal tract (BGIT) is a common gastrointestinal emergency. There is no consensus whether this condition should be admitted to medical or surgical discipline. Timing of presentation may also impact patient outcomes due to differences in healthcare resource availability. This study thus aims to investigate the impact of admitting discipline and timing of admission on patient outcomes in BGIT. Methods: A 2-year tertiary institution database was retrospectively reviewed. Outcome measures included 30-day mortality, 30-day readmissions and rebleeding requiring repeat endoscopic, angiographic or surgical interventions. Secondary outcome measures included time to endoscopy, percutaneous angiographic interventions and surgery. The effect of admission discipline (medical versus surgical) and time of admission (office-hours versus after office-hours) were analysed using a propensity-score-adjusted estimate. Results: A total of 1384 patients were included for analysis, medical (n = 853), surgical (n = 530); during office-hours (n = 785) and after office-hours (n = 595). After propensityscore-adjusted analysis, no significant differences in mortality or readmissions were noted between medical or surgical admissions. Patients admitted under surgery were less likely to sustain rebleeding (P = 0.004) for lower BGIT and had an earlier time to endoscopy for upper BGIT (P = 0.04). Patients admitted after office-hours had similar outcomes with those admitted during office hours apart from a delay in time to endoscopy (P = 0.02). Conclusion:For BGIT patients, admission to a surgical discipline compared to a medical discipline appeared to have at least equivalent patient outcomes. Patients presenting with BGIT after office-hours were more likely to experience a delay to endoscopy, although it did not affect patient mortality.