Monday, October 31, 2005

Drop in ETCO2

This was an interesting consult: 75 y/o woman with depression (lost her husband a month ago) and chronic back pain came in for an elective laminectomy. She received rapid induction with Propofol and succinylcholine and was intubated rapidly. She then had sudden bradycardia and hypotension with hypoxemia and her continuous end-tidal CO2 indicator dropped precipitously.
They cancelled the surgery and gave her dopamine and fluids. She had a rebound tachycardia with dopa, was given neosyn. and cardiology and I were consulted.
What other info would you want?

4 comments - CLICK HERE to read & add your own!:

Jon Mikel, M.D. said...

Actual or former smoker?
Previous medical history?
Drugs for treating depression/other disease (ex. cardiac failure)?
General inspection - Habitus exterior?

ASA/Goldman classification?

Plasma bicarbonate concentration?
Arterial blood gases?
Hemoglobin level prior induction of surgery?

Jennings said...

1. Where was the ETT? Maybe she was intubated into the right mainstem.
2. Other alternative: that the end tidal CO2 suddenly went down indicates that tube may never have been in the airway. Perhaps it was in the esophagus....

Baleeiro said...

She was quite obese, not on cardiac or pulmonary meds. Limited performance status because of the back pain and depression. Very remote TOB use. Pre-op EKG had an anterior LFBBB. Normal pre-op CBC. First ABG was 7.24 / 58.8 / 93.9.

DKeena said...

The timing of her decompensation suggests either an adverse reaction to the meds she received for induction, or a problem with her intubation/ventilation.

Any personal or FH of anesthetic rxn? Any exam evidence of anaphylaxis?
Malignant hyperthermia is a possibility, but I would not have expected her ETCO2 to drop, unless she had severe hypoperfusion. Any hyperthermia, muscle rigidity?

Hyperkalemia is also a possibility especially if she had significant neuropathy associated spinal stenosis? K? Underlying renal disease?

Propofol could certainly cause the hypotension and bradycardia, especially if she was dehydrated.

Assuming the tube was in position, what were her airway pressures? Did she have underlying obstructive Dz? AutoPEEP?