Week 5 - Complex Renal Health

Kidney anatomy

• 2 Kidneys​

• Retroperitoneal space​

• Nephrons (functional units) ​

• Glomerulus —> filter​

• Tubules —> reabsorb & excrete

Key Functions of the Kidneys ​

• Regulate pH, fluid and electrolyte balance ​

• Retains HCO3- and filters out H+​

• Na+ and K+ regulation ​

• Reabsorb & excrete water ​
  ​

• Role in Blood Pressure Regulation ​

• Renin, Angiotensin, Aldosterone (RAAS)​
  ​

• Excrete waste​

• i.e. protein metabolites like nitrogen and urea, water-soluble medication metabolites ​
  ​

• Secretes erythropoietin to stimulate RBC production ​

• Vitamin D synthesis for bone health​

Blood Pressure & the Renin Angiotensin​ Aldosterone ​System ​ (RAAS)

1. low BP + blood flow to kidneys —> renin release (from juxtaglomerular cells) 

2. Renin converts angiotensinogen (made by liver) —> Angiotensin I 

3. ACE converts ang I —> ang II

4. ANG II (POTENT vasoconstrictor) ALSO stimulates aldosterone (from adrenal cortex) + ADH (pituitary) + increase thirst 

Aldosterone

high = increase Na, fluid volume, BP, decrease U/O = more into blood instead of filtrate

low = decrease Na retention, FV, BP, increase U/O (diuresis)

Vasopressin or Antidiuretic Hormone

high = increase FV, BP, decrease U/O

low = decrease FV, BP, increase U/O 

Released from posterior pituitary gland (injury to gland can impact the release)

Renal Nursing Assessments​ - Risk Factors: Health Hx. & Family Health Hx. ​

• Comorbidities that increase risk of kidney damage​

  • Diabetes; Hypertension; Neuromuscular Conditions effecting bladder emptying(neurogenic bladder; Parkinson's or MS)​

  • type II DM, big comorbidity 

• Family history of kidney disease​

• Age (increased age = increased risk of damage)

Renal Nursing Assessments​ - Medication History

Identify medications that may be nephrotoxic​ = metabolism + excretion occur in kidneys

• NSAIDS (ex. Ibuprofen (Advil) & Naproxen)​

• Antibiotics (ex. Vancomycin)​

• Loop Diuretics (ex. Furosemide (Lasix) )​

• Contrast Dyes (for MRI)​

• Metformin ​= taken by diabetics (big comorbity for renal disease) 

• Chemotherapy​

Renal Nursing Assessments Physical examination - Urinary output

Micturition = voiding (normal = 30 mL/hr, or 1-2 L/day)​

• not routine measuring, only when needed (catheter, critical care)

Abnormal findings, may be sign of dysfunction:​

• Anurea —> no U/O​ = late stage symptom, dialysis for kidney disease

• Oligurea —> low U/O​

• Polyurea —>  Excessive U/O​ = diabetes, dysfunction in release of ADH

• Hematurea —>  blood in urine ​(glomerular injury)

• Proteinurea —>  protein in urine (glomerular injury)

Renal Nursing Assessments Physical examination S&S

• If the kidneys are not filtering fluid appropriately—likelygoing to manifest into signs and symptoms of fluid volume overload​

• ​pitting + peripheral edema, crackles in lungs, JVD, SOB, pulmonary edema --> frothy sputum

• Which can lead to HTN and even CHF

Renal Nursing Assessments​ Physical Examination: Pain​

​​Flank pain (back area) --> kidneys

flank + groin pain (referred) = kidney stones, UTIs (acute pain)

Chronic kidney disease = usually no pain, slow and progressive

Renal Nursing Assessments Physical Examination: Signs of Waste Build-Up

urea (nitrogen waste) build up 

GI​

• Nausea, vomiting, diarrhea​

• Abdominal discomfort and distension ​

• Ulceration —> bleeding (impacts plt aggregation + adhesion) 

Integumentary​

• Itching/skin irritation r/t waste product buildup​ in skin 

  • antihistamines + creams dont relieve (not allergy) = health teachings 

• Pruritus (itching) 

Neurological​

• Waste product build-up interrupts normal neurological functioning ​

• Early: lethargy, forgetfulness, mild confusion​

• Late: seizures, coma

Renal Nursing Assessments​ Labs

• Blood Urea Nitrogen (BUN) (bun USA, urea canadian) and Creatinine

  • Urea + creatinine (waste product of cellular function) --> waste products, shows core function of the kidneys​

• Hemoglobin = kidneys related to RBCs production ​

• ABGs = pH values, H+ ions excreted through kidneys​

• Na and K = filtered out through kidneys​

• Bone Health (Vit D and Calcium) = kidneys activate vit d (calcium absorption)

BUN and Creatinine

Waste products in body that are normally filtered by kidneys​

In kidney dysfunction—filtration is ineffective —>  increased waste in body

• serum creatinine = elevated BAD!

• BUN = elevated BAD! 

• Creatinine clearance / estimation of glomerular filtration rate = decreased BAD!

• GFR = decreased value BAD!

  • gfr is difficult to measure, use eGFR = 24 hr urine + blood draw

Hemoglobin

Erythropoietin is required to stimulate RBC production by bone marrow ​

Erythropoietin is produced by kidneys, in dysfunction —> decreased EPO

• Hgb decreased = bad 

ABGs

​

Kidneys regulate acid base balance by role in balancing HCO3- and H+​

Dysfunction —>  decreased ability to filter and excrete H+, H+ is acidic = metabolic acidosis ​

• pH decreased = acidosis 

• PaCO2 = may reflect compensation (increase in resp acidosis) 

• HCO3 = likely decreased to reflect renal involvement (metabolic acidosis) 

Electrolytes

​

Kidneys help to regulate fluids and electrolytes by filtering, excreting, and retaining as needed to maintain homeostasis ​

Dysfunction —>  abnormal filtration, excretion, retention​

• potassium = Elevated likely due to retention, and response to acidosis ​

• sodium = Elevated likely due to retention, and response to acidosis 

Bone health

Kidneys synthesize vitamin D into usable form in body, Vit D plays role inincreasing calcium levels in bones​

Dysfunction —> vitamin D levels decrease, calcium decrease​

• health teaching = more likely to break a bone 

Assessment Findings Summary​

Fluid/Electrolyte Imbalance​

-Fluid Volume Overload​

-decreased U/O​

-hematuria/proteinuria​

-Hyperkalemia ​

-Metabolic Acidosis​

​Waste Buildup​

-increased BUN/Cr​

-neurological changes​

-integumentary breakdown r/t itching​

-GI upset (N/V/D, ulceration)​

Flank Pain

Anemia (decreased Hgb)

Loss of Kidney Function​ Acute + Chronic

Acute: Acute Kidney Injury (also known as acute kidney failure)​

• Sudden onset ​

• Characterized by rapid decrease in urinary output ​

• Reversible *​

Chronic: Chronic Kidney Disease (also known as kidney failure) ​

• Progressive​

• Permanent nephron degeneration ​

• Irreversible ​

​

A nurse is assessing a client with acute kidney injury. Which of the following findings should the nurse report to the healthcare provider as a priority?​

A. Urine output of 60 mL over 4 hours​
B. Serum potassium of 6.2 mmol/L (ref = 3.5-5)​
C. Mild bilateral lower extremity edema​
D. Blood pressure of 146/84 mmHg​

B = ARRHYTHMIAS!!!! CARDIAC ARREST!!!

• output expected to be treated

• BP high but not immediate danger 

Which clinical finding in a client with chronic kidney disease (CKD) most clearly indicates worsening renal function?​

​

A) Hemoglobin of 115 g/L (ref=120 – 160 g/L)​

B) Blood urea nitrogen (BUN) of 8 mmol/L (ref= 2.1–8.0 mmol/L)​

C) Serum creatinine rising from 1.2 to 2.6 mg/dL(ref= 0.8-1.2 mg/dL)​

D) Slightly elevated white blood cell count

C

• indicative of kidney function, doubling v concerning 

Acute Kidney Injury (AKI) ​

• Sudden loss of renal function ​

  • Resulting in fluid, electrolyte and pH imbalances(metabolic acidosis), waste buildup​

  • impacting renal function < 3 months 

• Classifications/Causes--defined by origin of issue impacting function​

  • Prerenal (hypoperfusion of kidneys)​ - blood to kidneys

  • Intrarenal (damage to kidney tissues) ​

  • Postrenal (obstruction of urine flow)​ - renal pelvis 

• Goal —>  avoid death & minimize long-term kidney dysfunction ​

Acute Kidney Injury (AKI) ​- Prerenal

Prerenal (hypoperfusion of kidneys)​

• 70% of cases​

• Fluid volume deficit​

• NSAID use can decrease renal perfusion ​

• Diuretics decrease fluid volume, which can decrease blood volume, which can decrease perfusion ​

• Low BP

Acute Kidney Injury (AKI) ​- Intrarenal 

Intrarenal (damage to kidney tissues) ​

• 10% of cases​

• Think ischemia, inflammation, toxins, necrosis​

• Nephrotoxic medications ​

• Immune reaction

Acute Kidney Injury (AKI) ​ - Postrenal

Postrenal (obstruction of urine flow) ​

• 20% of cases​

• Tumours​

• Kidney stones​

• Benign prostatic hypertrophy (enlarged prostate)

Get rid of obstruction, could use catheter 

AKI: Nurse’s Role in Prevention ​

Monitor kidney function and act when identifying concerns with function​

Know your drugs —>  risk of nephrotoxicity ​

• heart failure - diuretics (can be harmful to kidneys esp in AKI)

Follow Blood Transfusion Protocols – transfusion reactions can cause AKI​

Prevent Hypoperfusion of Kidneys by:​

• Provide Adequate Hydration—prevent dehydration in circumstances with increased risk [ex—surgery, nephrotoxic medications, advanced age]​

• Treat hypotension promptly: Address the cause of hypotension & shock(i.e. volume or infection)​

Prevent Infections: *Catheter care​

Acute Kidney Injury (AKI) Phases​

1. Initiation - inital insult (hrs to days after) 

2. Oliguria - rapid reduction in urine output, increase CR, BUN (pruritus), K (hyperkalemia) (1-2 wks, sometimes longer) 

3. Diuresis - tissues return to function, normal U/O (days to wks) 

4. Recovery - labs normalize (> 3 months) 

Interventions = catheters, pressors, increased fluid volume

AKI Goals of Care​

• Identify underlying cause, for example:​

  • if nephrotoxic medication, stop the med​

  • if FVD, start fluid resuscitation​

• Dialysis to support filtering​

• Diuretic medications to stimulate function (only if we have enough fluid on board! Don’t give diuretics if we are still in FVD—or could = hypovolemic shock)​

  • very carefully 

AKI Nursing Interventions​

• monitor fluid and electrolyte balance 

  • Fluid resuscitation​

  • Hyperkalemia prevention & recognition ​

  • I/O monitoring, U/O monitoring (amt + characteristics of urine), Daily Weights

• Infection prevention 

• promote pulmonary function

• psychosocial support 

AKI: Continuous Renal Replacement Therapy

• type of dialysis 

• short term —> gives kidneys break to allow for reversal + healing 

• Filters extracellular fluid​

  • Removes H2O, lytes, solutes through hemofilter ​

• Clears urinary toxins ​

• AKI in ICU​

• Different types

The nurse is caring for a client diagnosed with acute kidney injury (AKI). Which of the following assessment findings and laboratory results are consistent with this condition? Select all that apply.​

​

A. Urine output of 200 mL in 24 hours​
B. Serum creatinine level of 3.1 mg/dL(ref= 0.8-1.2 mg/dL)​
C. Blood urea nitrogen (BUN) level of 4 mmol/L (ref= 2.1–8.0 mmol/L)​
D. Generalized edema​
E. Hyperkalemia​
F. Increased serum calcium

A, B, D, E

A: decrease output (24 hrs) ​

B: not filtering out appropriately, build up ​

C: should be higher levels, waste build up ​

D: Fluid volume overload ​

E: not able to filter out ​

F: decreased due to decreased vitamind D synthesis ​

Chronic Kidney disease - there is no cure

• Preventative measures

• slow the progress, 

• severe disease

• dialysis or transplant

• death Chronic Kidney Disease: Stages ​

Chronic Kidney Disease: Stages ​

stage 1: eGFR > 90, Normal BUN/Cr​ Asymptomatic

stage 2: eGFR 60 - 89​, Elevated BUN/Cr​, Hypertension

stage 3: eGFR 30 - 59, Elevated BUN/Cr​, Hypertension, anemia, fatigue

stage 4: eGFR 15 - 29​, Elevated BUN/Cr​, Hypertension, anemia, fatigue, edema, metabolic acidosis

stage 5: eGFR < 15, Elevated BUN/Cr​, Kidney Failure

***Impacts renal function >3 months!!

Assessment Findings Summary CKD ​

Fluid/Electrolyte Imbalance​

-Fluid Volume Overload​

-decreased U/O​

-hematuria/proteinuria​

-Hyperkalemia ​

-Metabolic Acidosis​

​Waste Buildup​

-increased BUN/Cr​

-neurological changes​

-integumentary breakdown r/t itching​

-GI upset (N/V/D, ulceration)​

Flank Pain

Anemia (decreased Hgb)

Increased Stages =exacerbation S/S (gets worse)

CKD Nursing Priorities

Monitor fluid and electrolyte balance

• Hyperkalemia prevention & recognition ​

• I/O monitoring, U/O monitoring, DailyWeights ​

• Manage BP; Monitor for HT Crisis (Headache, NV, Δ in mental status)

Infection prevention 

• Integument health ​

• Edema & uremic pruritus ​

• ↑ skin breakdown risk

Avoid nephrotoxic medications 

• Be aware of dosing for any meds metabolized/excreted by kidneys; risk of drug toxicity is increased

Psychosocial support 

CKD Interventions Dietary - protein, Na, K, Phosphate ​

Protein Restriction: ​

• Protein digestion creates nitrogenous waste/urea as bi-products – which remember these kidneys are having a hard time getting rid of!​

• Limit excess protein – remember this can’t mean eat NO protein, as we need protein to survive.​

Na and K restriction ​

• Prevent fluid retention and further electrolyte imbalance ​

Phosphate Restriction​

• Remember that vit D synthesis is reduced, which reduces Ca, which causes bone health to decrease? ​

• Excess Phosphate further draws Ca out of bones – making these weak bones even weaker!

CKD Interventions Dietary - High Na, K, Ph foods

High Na Foods: ​

• Added salt ​

• Canned, processed foods ​

• Sauces: soy sauce, prepared dressings​

​

High K Foods: ​

• Dark leafy greens​

• Bananas, cantaloupe, oranges​

• Potatoes​

• Green produce: Broccoli, avocados, kiwi​

​

High Ph Foods: ​

• Fish​

• Eggs​

• Milk, cheese​

• Whole grains​

CKD Pharmacological Interventions

Issue​	Medication to Treat​
Hypertension (either due to dx as risk factor, or from FVO)​	Antihypertensives ​
Blood glucose (diabetes as risk factor)​	Antihyperglycemic agents​
Anemia​	Hematopoietic growth factors, Iron ​ ​
Vit/Mineral Imbalances​	Calcium, Vit D supplements ​ Phosphate or K binders ​
Fluid volume overload​	Diuretics*​ - careful

ACEI, ARBS (influencing the RAAS) --> antihypertensive

Diuretics Kidney Disease 

Loop + thiazide = potassium wasting = hypokalemia

Spironolactone = potassium sparing = hyperkalemia 

• usually not given for ppl w CKD - arrhythmias 

CKD Patient Education​

Goal: Delay Progression​

• Control Blood Sugars​

• Control Blood Pressure ​

• Diet​

• Smoking cessation​

• Alcohol intake​

• Weight reduction​

• Exercise ​

• Avoid nephrotoxic meds (*NSAIDs, available over the counter)​

Dialysis

• Intermittent treatment to provide extracellular fluid filtration ​

• Based on the principles of diffusion, osmosis and filtration: ​

  • For example, with hemodialysis —>  Blood is removed from body and moves through dialysis machine​

  • Blood is exposed to dialysate solution that is specifically compounded to draw out specific amounts offluids/electrolytes/waste products​

  • “Cleaned” blood returns to the body​

• Required when kidney function drops below baseline required to maintain fluid/electrolyte balance ​

• Goal: remove fluid volume excess, filter electrolytes, filter waste​

• Required routinely, up to 3x/week to manage balance​

Dialysis Assessment ​

• Pre vs Post Assessment – compare to identifyimprovement​

​

1. Vital Signs: BP/HR/RR (fluid status), temp(infection)​

2. Fluid Balance (Weight)​

3. Labs—can adjust dialysis settings based on electrolytes, to add or remove as needed​

Peritoneal Dialysis ​

• HIGH INFECTION RISK!

• Filter via passive filtration through peritoneal cavity​

• Fill peritoneal cavity with hypertonic solution via insitu catheter, water moves into peritoneal cavity via osmosis, dwells —> allow waste + excess water from blood into dialysis solution —> cavity drained ​

• Gravity or continuous cyclic​ (machine) 

• one catheter (to minimize infection) —> connects to solution bag + drainage (not at same time) 

Peritoneal Dialysis ​- Nursing actions 

• Warm solution before administration for comfort​

• Aseptic technique for infection prevention​

  • Wash hands and wear mask before accessing catheter, clean catheter access point, use care when spiking bag​

• Monitor for complications (e.g. peritonitis inflammation of peritoneum)

  • Discomfort for patients: abdominal distension

Hemodialysis ​

• Attach to dialysis machine via fistula​

• AV Fistula: Artery-Vein fusion to create large enough vessel to filter all body fluids​

• Fistula care and assessment​

  • Avoid BP on arm ​

  • You may hear a “bruit” over site due to increased flow​

  • Routine Neurovascular assessments​

  • Do not use for other purposes​ (blood draws etc. ONLY dialysis) 

Dialysis: Complications - hypotension

• Occurs from rapid shift of fluid volume​

• May be associated with lightheadedness, nausea, vision changes ​

• If patients are experiencing this,the provider needs to be notified in order to change the dialysis settings to reduce fluid volume  being removed, or make adjustments to antihypertensive medication regimes around dialysis treatments

Dialysis: Complications​ - Thrombosis or Air Emboli​

• To prevent thrombosis, blood thinners (typically heparin) is mixed with blood before moving into dialyzer​

• Nurses should use good practice when priming lines and accessing fistula to prevent air emboli in hemodialysis​

Dialysis: Complications​ - Hand ischemia​

• S/S: paresthesia in hand, coolnessin hand, pain​

• Only occurs in hemodialysis patients with AV fistula​

• Occurs due to diversion of blood flow in fistula that results in lack of perfusion to hand past fistula​

• Notify provider as fistula may require re-constructing​

Dialysis: Complications​ - Infection

• In hemodialysis; infection can occur due to poor technique when working with dialyzer machine, or accessing fistula. To prevent –use aseptic technique​

• In peritoneal dialysis, this is called “peritonitis” and occurs from lack of aseptic technique when accessing catheter.​

Dialysis: Complications​ - Disequilibrium Syndrome​

• S/S: N/V, confusion, headaches, restlessness, twitching, seizures, hypotension​

• Rare complication from changes to fluid/electrolyte balance in body​ = cerebral edema 

• Electrolytes/waste are removed from blood during dialysis but can remain in higher concentrations in nervous system tissues, so fluid shifts into brain =cerebral edema​

• If suspected -> slow/stop dialysis treatment and transfuse hypertonic solution to draw fluid out of brain​

• Most common after missed treatments when waste/electrolyte imbalances are highest​

Transplant ​

• Healthy kidney replaces ​

• Most effective treatment for stage 5​

• Immunosuppressants for life​

The nurse is caring for a client with Stage 4 chronic kidney disease. Which of the following assessment findings and interventions are appropriate to anticipate or implement? Select all that apply.​

​

A. Monitor for signs of hyperkalemia such as muscle weakness and ECG changes​
B. Encourage a high-protein diet to support nutritional status​
C. Assess for signs of fluid overload such as crackles and peripheral edema​
D. Prepare the client for possible erythropoietin administration​
E. Monitor calcium and phosphate levels regularly​
F. Administer nephrotoxic medications with meals to reduce absorption

ACDE

A nurse is caring for a client who is currently receiving a hemodialysis session. The nurse notes the client is slouching in the bed, upon assessment the client reports a headache, nausea, and restlessness. The client’s vital signs are within normal limits, but the client appears confused when compared to their baseline. Which of the following actions should the nurse take first?​

​

A. Notify the healthcare provider of suspected cerebral edema​

B. Administer an antiemetic as prescribed​

C. Elevate the head of the bed and dim the lights​

D. Stop the dialyzer machine promptly

D.