Nursing Care and Pathophysiology of Renal Calculi (Kidney Stones)

This lesson is going to cover Renal Calculi, which is just the fancy name for Kidney Stones.

So renal calculi are stones that form in the urinary tract and can get lodged in the kidneys. They could be small and form here in the cortex, or they could accumulate and be larger and form within the medulla here. Stones form because chemicals in the kidneys get concentrated and can crystallize or calcify into these stones. Common chemicals that cause calculi are calcium, oxalate, and uric acid - this is especially common for patients with Gout. So what causes this? Well, anything that causes these chemicals to get concentrated. That might be that the patient is taking IN too much of it - like a diet high in calcium or vitamin D, or high in protein or purines that can cause an increase in uric acid. Dehydration can also cause concentration of the substances in the kidneys, as well as urinary stasis. That’s when the urine gets stagnant in the kidneys - which could be because of immobility, obstruction, or even infections.

Now, you can imagine, any time a stone forms in the kidney it will cause a lot of pain and could cause an obstruction. So we see sudden, SEVERE pain that starts in the back and radiates around to the flank, and to the front to the groin and bladder. The could also even have a dull ache over their kidneys, which is the flank area. This type of pain is sometimes referred to as “renal colic”. We may also see signs of a Urinary Tract Infection like cloudy urine or a high fever. We could also see hematuria which is blood in the urine. And as the stone gets lower into the urinary tract and into the urethra, patients may also complain of perineal pain and like they can’t start a stream. Unfortunately, most of the time, the only way to resolve this is for the patient to ultimately PASS this stone in their urine. BUT, if it’s too large, we do have some other options for removal.

The most common thing we use is what’s called extracorporeal shockwave lithotripsy. This is when we use shockwaves from the outside of the body (that’s what extracorporeal means) and those shockwaves will break up that stone into tiny particles that are easy to pass out through the urethra in the urine. We can also do a lithotomy, which is surgical removal of the stone, or we could insert a nephrostomy tube to divert the urine externally while we work to break up the stone. We can also do a uroscopy, which is when we insert a camera up through the urethra and through the bladder and the ureters to find the stone and physically remove it with the cytoscope. When I say cytoscope or cytoscopy I’m talking about a camera looking into the bladder.

As far as nursing care, our number one priority is going to be to address their pain with analgesics. Guys, they compare the pain of kidney stones to childbirth, it’s horrible. We also want them to increase their fluid intake to flush out the stones and restrict any dietary intake of things like calcium or purines so they don’t develop anymore stones. We will actually strain all urine so that we can catch the stones. You can see here that sometimes they have multiple tiny stones that are causing problems, so we want to strain them out. We do this partly so we know when we’ve passed the stones, but also we will test them to see what they’re made of. If they’re mostly calcium, the patient knows that they need to continue to decrease their calcium intake so they can reduce the risk of developing more stones. And then, of course, with the possibility of obstructions, the patient could develop infection or even acute kidney injury, so we’re going to monitor vital signs and for signs of infection.

As you could have guessed, our priority nursing concepts for a patient with renal calculi are going to be comfort and pain control, infection control and prevention, and elimination. Make sure you check out the care plan attached to this lesson to see more detailed nursing interventions and rationales.

To recap, kidney stones are formed in the kidneys or urinary tract because substances like calcium or uric acid will get concentrated and crystallize. These stones can get lodged in the urinary tract causing severe pain and possible urinary tract infections. Unfortunately most patients will have to just pass these stones in their urine, but we could also use shockwave lithotripsy or surgical removal of the stones if needed. We encourage patients to increase their fluid intake and avoid whatever it is that caused their stone so that we can flush the stones out of their kidneys.
Okay, guys, that’s it for renal calculi, or kidney stones. Make sure you check out all the resources attached to this lesson to learn more. Now, go out and be your best selves today. And, as always, happy nursing!