Question 1a and Question 1d from the second paper of 2004 ask about the approach one might take to the undifferentiated overdose patient. The approach suggested below has been plagiarised from the excellent article by Daly, Little and Murray (EMJ, 2006). I am sure they will forgive me for cut-and-pasting the entire content of their Box 1, and using it as the skeleton for this chapter.
Well, this is an ED thing. Typically, the unconscious or semiconscious and uncooperative patient is brought via the ambulance, after they were found in a pool of vomit / surrounded by pill packages / in the company of a cask of wine and a suicide note. The ED staff then proceed with a series of stereotypical behaviours.
At some stage during this process, a rescue agent may appear to be appropriate. The list of such agents is made available in the summary of toxins and their antidotes. They may include naloxone for opiates, sodium bicarbonate for tricyclics, intralipid for local anaesthetics, hydroxycobalamine for cyanide, and so forth.
Taking into account:
What is the point, one might ask? Taken directly from the EMJ article:
A) - If in doubt, keep them intubated.
B) - Keep them ventilated with a mandatory mode initially; ensure that the minute volume is enough to help them compensate for the acidosis they were experiencing. Classically, the patients with salicylate overdose end up dying suddenly if they are ventilated slowly, and the ensuing respiratory acidosis improves the lipid solubility and CNS penetration of their serum salicylate. Specific strategies may apply in certain circumstances, particularly in the case of paraquat toxicity (where oxygen has a known deleterious effect)
C) - haemodynamic support as required - this may range from ECMO to beta blockade and nitroprusside
D) - nothing specific can be said except the use of benzodiazepines is encouraged in the literature, both as a means of seizure prophylaxis and as a means of controlling a potential impending withdrawal syndrome. Practically, long-acting benzodiazepines are not desirable, as they obscure the neurological findings.
E) - Normal electrolyte concentrations protect the patient from such badness as torsade
F) - Forced diuresis may not be indicated for virtually any intoxication apart from perhaps cyclophosphamie, or in the case of rhabdomyolysis. However, maintaining a good urine output promotes renal clearance of drugs which benefit from it.
G) - There is rarely a firm contraindication to nutrition
H) - There is rarely a requirement for transfusion, but exchange transfusion is a possible solution to severe methaemoglobinaemia.
I) - antibiotics are rarely required; extremes of temperature may require cooling or heating.