35 year old Aboriginal female presents with a 2/52 history of weakness, thirst and nausea. Presenting today as now unable to lift hands to mouth to drink or feed herself. Admitted 3/12 ago with something similar but doesn’t know what it was and her medical notes are not immediately available. No other past medical history of note.
Examination reveals a quiet, dehydrated lady with generalised non-lateralising weakness in all 4 limbs.
| HR | 75 | /min | |
| BP | 90/50 | mmHg supine | |
| Temp | 37.1 | oCelsius |
Bedside venous blood gas results included:
| Reference Range | ||||
| FIO2 | 0.21 | |||
| pH | 7.25 | 7.35-7.45 | ||
| pCO2 | 35 | mmHg | 35-45 | |
| pO2 | 234 | mmHg | 80-95 | |
| HCO3 | 15.0 | mmol/L | 22-28 | |
| Base Excess | -11 | -3 to +3 | ||
| Na+ | 141 | mmol/L | 134-146 | |
| K+ | 1.1 | mmol/L | 3.4-5.0 | |
| Cl- | 116 | mmol/L | 98-106 | |
| Glucose | 5.4 | mmol/L | 3.5-4.5 |
Questions:
| a. | What is her primary acid/base disorder?What is her anion Gap? | (40%) |
| b. | Describe the features of the ECG | (40%) |
| c. | List your differential diagnoses | (30%) |
12 Lead ECG
ANSWERS and further discussions
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