QuestionSBA
QuestionChoice
Loss of HCl (stomach acid) can occur through high volume vomiting and results in the depletion of the body's H+ ions. This can result in a metabolic alkalosis. However, this is an unlikely cause of this patient's presentation as he has presented with a respiratory alkalosis. The ABG results of a metabolic alkalosis appear as follows:

* Elevated pH
* Normal PaO2
* Normal PaCO2 (or increased in compensation)
* Elevated HCO3-
* Elevated base excess
10000393
c
Loss of hydrogen ions
QuestionChoice
Benzodiazepines suppress the respiratory centres, causing respiratory acidosis. This patient has presented with respiratory alkalosis caused by stimulation of the respiratory centres due to salicylate overdose. Respiratory suppression results in the retention of CO2, which causes acidosis. The ABG results of a respiratory acidosis appear as follows:

* Elevated pH
* Reduced PaO2
* Elevated PaCO2
* Elevated HCO3- if compensated
* Elevated base excess if compensated
10000394
d
Benzodiazepine overdose
QuestionChoice
Diabetic ketoacidosis (DKA) presents with metabolic acidosis, whereas this patient suffers from respiratory alkalosis, therefore DKA cannot be the cause of this patient's presentation. The ABG results of a metabolic acidosis typically appear as:

* Reduced pH
* PaO2 normal or may be increased if compensation
* PaCO2 normal or may be decreased if compensated
* Reduced HCO3-
* Low base excess
10000392
b
Diabetic ketoacidosis
QuestionChoice
This patient has presented with a respiratory alkalosis secondary to salicylate poisoning. In the early stages of salicylate poisoning, stimulation of respiratory centres results in respiratory alkalosis as CO2 is blown off before metabolic acidosis manifests later due to the direct toxicity of salicylates. Salicylate poisoning presents with hyperventilation, nausea, vomiting, abdominal pain, tinnitus, confusion, and tachycardia. Severe poisoning can cause cerebral and pulmonary oedema, followed by death.
10000391
a
Salicylate poisoning
QuestionChoice
Similarly to benzodiazepine overdose, opiates cause suppression of the respiratory centres. This results in hypoventilation and subsequent CO2 retention, which manifests as respiratory acidosis.
10000395
e
Opiate overdose
Concept
Chapter
2693
3756
ABG Analysis
Topic
142
Nephrology
12625
A 24-year-old male is brought to the emergency department by his flatmate. The flatmate reports that he found the patient vomiting and confused 40 minutes ago and immediately brought him to the hospital. On assessment, the patient is confused and is only able to report that he feels nauseous and unwell. You note that his respiratory rate is 27 and his heart rate is 92bpm. You perform further investigations, including an arterial blood gas. The results are as follows:

* pH: 7.48 (7.35 - 7.45)
* Pa02: 14kPa (11 - 13)
* PaCO2: 3.1kPa (4.7 - 6.0)
* HCO3-: 25 (22 - 26)
* Base excess: +2 (-2 - +2)

Which of the following is the most likely cause of this patient's presentation?
a