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
- the kitchen sink….
- 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
- Addison’s Disease
- Drugs (NSAIDS, ACEi, potassium-sparing diuretics)
- 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.
Divided into three phases;
- Membrane stabilisation
- Intracellular shift of K+
- Removal / Excretion of K+
- 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.
- 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,