Environmental

A 30-year-old man is brought to the emergency department by paramedics after collapsing at the 30 km mark of a marathon on a warm, humid summer day (ambient temperature 34°C). He was noted to be confused and stumbling prior to collapse, and bystanders report he had stopped sweating. On arrival his GCS is 8 (E2V2M4), he is agitated when roused, and he has generalised muscle rigidity. Observations are: temperature 41.5°C (tympanic), BP 70/40 mmHg, HR 148 bpm, RR 28/min, SpO₂ 94% on room air. His skin is hot and dry to touch. Point-of-care glucose is 4.8 mmol/L. Which of the following is the most appropriate immediate management step?

A 30-year-old man is brought to the emergency department by paramedics after being found unresponsive in a public toilet by a friend. On arrival his observations are: RR 6/min with shallow, irregular breaths, SpO2 88% on room air, HR 58/min, BP 100/60 mmHg, temperature 36.1°C. He has a GCS of 8 (E2V2M4), bilateral pinpoint pupils, and cyanosed lips. Examination reveals multiple old and fresh track marks over both antecubital fossae. His friend reports he has a history of intravenous heroin use and was last seen well approximately 30 minutes earlier. There is no evidence of trauma and a bedside glucose is 5.4 mmol/L. What is the most appropriate immediate management?

A 30-year-old woman is brought to the emergency department by ambulance 2 hours after her partner found her with an empty packet of amitriptyline tablets, having ingested an estimated 1.5 g in a deliberate self-poisoning. She is drowsy but rousable to voice (GCS 13/15). Observations reveal BP 88/54 mmHg, HR 122 bpm, RR 18/min, SpO2 97% on room air, and temperature 36.8°C. Examination shows dilated pupils, dry mucous membranes, a palpable bladder and reduced bowel sounds. A 12-lead ECG demonstrates sinus tachycardia with a QRS duration of 130 ms and a terminal R wave in aVR. Which of the following is the most appropriate next step in management?

A 25-year-old man is brought to the emergency department by paramedics after being pulled from a cold lake, where he had been submerged for approximately one minute following a fall from a boat. He was reportedly conscious on retrieval and has been breathing spontaneously throughout transport, though bystanders report a brief period of coughing and spluttering at the scene. On arrival he is alert and orientated with GCS 15. Observations are: temperature 35.6°C, heart rate 92 bpm, blood pressure 118/76 mmHg, respiratory rate 18/min, and SpO2 97% on room air. Chest auscultation is clear bilaterally, and there is no stridor, wheeze or accessory muscle use. He denies chest pain or dyspnoea and asks to go home. Which of the following represents the most appropriate next step in his management?

A 25-year-old previously well male is trekking in the Nepalese Himalayas. He ascended from 2800 m to 4800 m over a single day, skipping the recommended rest days because of time pressure. On day 2 at altitude he develops a severe, throbbing headache that fails to settle with paracetamol and rest. His companions note that he has become unsteady on his feet and increasingly confused, repeating questions and struggling to follow simple instructions. He denies chest pain but reports mild exertional dyspnoea. On examination his temperature is 36.8°C, heart rate 104 beats/min, respiratory rate 22/min, blood pressure 118/76 mmHg and oxygen saturation 84% on room air. GCS is 14 (confused, disoriented to time). There is no facial droop, limb weakness or sensory deficit, but he is unable to perform tandem gait and finger-nose testing reveals mild dysmetria bilaterally. Chest auscultation is clear. What is the most likely diagnosis?

A 25-year-old man is brought to a rural emergency department after being bitten on the lower leg by a snake while gardening; he did not see the snake clearly but describes a brief sharp pain followed by two puncture marks. His mate applied a pressure immobilisation bandage promptly and he was transported without ambulating. On arrival the bandage is removed after baseline bloods are taken: INR, APTT and fibrinogen are normal, CK is normal, and there is no local swelling, bleeding from puncture sites, ptosis, or other neurological abnormality. He is admitted for observation with serial examinations and coagulation studies at 1, 6, 12 and 24 hours, all of which remain normal, and his CK stays within the normal range throughout. Vital signs have been stable and he has remained completely asymptomatic. At 24 hours he feels well and wants to go home. The MOST appropriate next step in management is: