8 mmol/L) and rapidly evolving acute

kidney injury due to acute tubular necrosis (ATN; initial creatinine 120umol/L, peak at 1210umol/L on day 4 post-diving accident). The diagnosis of ischaemia-induced ATN was supported by a high urinary fractional sodium excretion of 5.5%, elevated LDH (486U/L [125–250]) and a MAG3 scan in keeping with ATN. The absence of myoglobinuria and only moderately elevated creatine kinase (maximum 893U/L [30–170]) made rhabodmyoloysis-induced find more ATN unlikely. He received supportive care with intravenous hydration, sodium bicarbonate and 100% oxygen followed by 7 sessions of hyperbaric therapy and recovered fully without needing dialysis. Conclusions: Arterial air embolism occurs when expanding gas ruptures alveolar capillaries (pulmonary barotrauma) and enters the arterial circulation as a result of rapid decompression. Clinical manifestations depend on the site of embolization and usually include neurological and respiratory symptoms but can also

involve the muscles, skin, mesenteric circulation and as shown in this case the kidneys. The diagnosis is made on clinical grounds since gas bubbles are rarely detectable on imaging. Best first aid for decompression illness is 100% oxygen therapy and supportive care but early transfer to a hyperbaric treatment unit is important as symptoms may evolve over time as in our patient. 277 HYPERKALEMIA INDUCES FAILURE OF PACEMAKER FUNCTION IN HEMODIALYSIS PATIENT N AUNG, S MAY Tamworth Base Hospital, New South Wales, Australia Background: Hyperkalemia may cause cardiac pacemaker Vadimezan cell line malfunctioning due to a reduction of the electronegativity of the resting myocardial potential. Both sensing and capture mechanisms could be temporarily affected, with possible life-threatening effects. Case Report: Mr. DT, 50 years old male with background history of End Stage Renal Failure due to diabetic nephropathy on maintenance hemodialysis, Aortic Valve Replacement, Pacemaker for third degree AV block presented to ED in a small rural hospital with lethargy and unwell. BP 82/50 mmHg, HR 22/min. ECG showed significant bradycardia

20/min with failure of rhythm to capture the pacing. Arrangement was made for urgent transfer to Metropolitan unit with pacemaker malfunction. Subsequent Urease result: K 7.6 mmol, BSL 52.8 mmol. Repeat ECG show similar finding with no classic hyperkalemia changes. Patient was treated with usual medications for hyperkalemia and commenced on insulin infusion. At the same time, Haemodialysis was commenced. After 30 minutes on dialysis, patient’s vital sign improved to BP 100/70 mmHg, HR 65/min with ECG showing normal ventricular paced rhythm. Conclusions: Hyperkalemia is a cause of acute pacemaker malfunction without classical hyperkalemia ECG change due to a failure of pacemaker sensing and capturing. Acute treatment of hyperkalemia will restore pacemaker function.