fbpx

generally unwell (part 2)…

For those joining the story for the first time, you can catch up here….

My interpretation of the ECG;

Sinus rhythm with 1st degree HB, an ‘odd’ axis. Wide complex QRS (~140-160ms) with symmetrical tall T-waves.
? Hyperkalaemia. Needs urgent bloods….

The nurse returns…

No one can place an IV or take bloods from her. So off you go, USS in tow to the bedside.

IV placed; bloods taken; urgent VBG to the iStat…..


Transfer to Resus & treated with….

      • Calcium Gluconate 2x 10mLs
      • Sodium Bicarbonate
      • Insulin + Dextrose
      • Salbutamol
      • Resonium
      • the kitchen sink….

The Review:

CRITICAL HYPERKALAEMIA

The causes:

  • Factitious hyperkalaemia (most common, secondary to haemolysed sample) –>; urgent recheck.
  • Increased K+ intake (meds, supplements, stored blood) Rare !
  • Transcellular shifts (acidosis, hypertonicity, beta blockers, digoxin toxicity, exercise)
  • Cellular injury (crush injury, burns, rhabdomyolysis, DIC, tumour-lysis syndrome).
  • Impaired excretion
      • Acute Renal Failure (Pre, intra & Post-renal causes)
      • Tubular defects
      • Hypoaldosteronism
      • Addison’s Disease
      • Drugs (NSAIDS, ACEi, potassium-sparing diuretics)

The ECG:

  • Mild Elevation (5.5 – 6.5 mmol/L)
      • Tall symmetrical, peak T-waves
  • Moderate Elevation (6.5 – 8.0 mmol/L)
      • P-wave amplitude decreases –>; loss of P-wave
      • PR interval increases
      • QRS widens
  • Severe Elevation (>; 8.0 mmol/L)
      • Intraventricular, fascicular or bundle-branch blocks
      • QRS widens further –>; progression to ‘Sine wave’.
      • VF –>; Asystole.

The Management:

Divided into three phases;

  1. Membrane stabilisation
  2. Intracellular shift of K+
  3. Removal / Excretion of K+

Drug options:

  • Calcium Gluconate (10mL = ~ 2.2mmol Ca2+) / Chloride (10mL = ~ 6.8mmol Ca2+)
      • Onset 1-3 mins / Duration 30-50 mins.
  • Sodium Bicarbonate (50-100mL 8.4% solution)
      • Onset 5-10 mins / Duration 1-2 hours.
  • Insulin / Dextrose (~ 5-10 units insulin + 25g glucose)
      • Onset 30 mins / Duration 4-6 hours.
  • Beta-agonists (5-20mg Salbutamol nebulised)
      • Onset 15-30 mins / Duration 2-4 hours.
  • Frusemide (~40mg, only if passing urine)
  • Exchange Resins (15-30 grams, PR or PO)
      • Onset 1-2 hours / Duration 4-6 hours.
  • Dialysis
      • Indications include pulmonary oedema & fluid overload, profound acidosis, hyperkalaemia (esp with associated rhabdomyolysis), uraemia and altered mental status.

As always –>; correct & treat the underlying pathology or precipitating cause !

SO…. what happened to our lady ???

ECG post treatment:

  • An IDC is placed & only 10mL of clear urine is aspirated (urinalysis unremarkable).
  • Bedside USS shows at least moderate hydronephrosis –>; CT (non-contrast) booked

  • She is taken to ICU for urgent haemodialysis… Overnight she is anuric.
  • The following morning she heads to the operating room…

  • Her very thin left ureter is stented. The dilated right ureter is obstructed distally & unable to get stented.
  • She receives a percutaneous nephrostomy a few hours later.
  • Within 48 hours her renal function has returned to baseline…..

The Diagnosis: Acute Renal Failure secondary to obstructive uropathy from a previously undiagnosed pelvic malignancy…

Finally an ECG to reinforce the notion that not all patients behave the same at the same K+ levels….
Here is one I dug up from the collection with a K+ of only 7.8

I know the topic this week is a little pedestrian, but it is so common that I felt a refresher would be helpful to keep some of this stuff in active memory….

I also think its a good example of how diligent and thorough we need to be throughout our entire shift in the ED, no matter how hectic the environment becomes !

Hope you found it useful,

CHRIS.

REFERENCES.

1) Chan TC, Brady WJ, Harrigan RA, Ornato JP, Rosen P. ECG in Emergency Medicine and Acute Care. Elsevier Mosby 2005.
2) Mattu A and Brady W. ECGs for the Emergency Physician 1.
3) Rosenʼs Emergency Medicine. Concepts and Clinical Approach. 7th Edition

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.