Presentation on theme: "Emergencies in Renal Failure and Dialysis Patients Tintinalli chapter 93."— Presentation transcript:
Emergencies in Renal Failure and Dialysis Patients Tintinalli chapter 93
ESRD: irreversible loss of renal function, accumulation of toxins and loss of internal homeostasis. Uremia: clinical syndrome resulting from ESRD.
Epidemiology 1999=89,252 new cases/424,179 patients being tx for ESRD Causes: DM=#1, HTN=#2 Therapy: dialysis=70% – transplants=30% ESRD deaths: 50% cardiac causes. –10-25% infectious Survival rates for 1,2,5 yrs= 79, 65, 34 % respectively
Pathophysiology of Uremia Excretory Failure: causes >70 chemicals to elevate. Urea= major breakdown of proteins. Limit protein intake Biosynthetic Failure: loss of hormones 1,25(OH)3 vit D3 and erythropoietin. –85% of erythropoietin produced by kidney. – Vit. D3 deficiency= secondary hyperparathyroidism, renal bone disease.
Pathophysiology of Uremia Regulatory Failure: over secretion of hormones, disruption of normal feedback mechanisms
Clinical Features of Uremia Neurologic complications: Subdural hematoma: 3.5% of ESRD, HTN, head trauma, bleeding dyscrasias, anticoagulants, ultrafiltration. Uremic Encephalopathy: nonspecific centreal neurologic symptoms, responds to dialysis.
Neurologic complications: Dialysis Dementia: like uremic encephalopathy but progressive and fatal, seen after 2 years on dialysis Peripheral neuropathy: >50% of HD patients. “glove and stocking pattern”, improves after transplant Autonomic dysfunction: common; dizzy, impotence, bowel dysfunction.
Cardiovascular complications: prevalence is greater in ESRD d/t pre-existing conditions, uremia, toxins, high lipids, homocystine, hyperparathyroidism, dialysis related conditions
General population CAD:12% LV hypert. 20% CHF5% ESRD 40% 75% 40%
Creatine protein Kinase &MB, Troponin I and T…….NOT significantly elevated in patients undergoing regular dialysis, have been shown to be specific markers in these patients.
HTN: 80-90% of ESRD starting dialysis. d/t volume, vasopressor effects of kidney, RAS system. Tx initially w/ volume control CHF: HTN #1 cause in ESRD. Uremic cardiomyopathy: dx of exclusion when other causes of CHF ruled out.
Pulmonary Edema: fluid overload, MI. –Tx w/ O2, nitrates, ACE inhib, morphine, diuretics. Can also use phlebotomy, dialysis. Cardiac Tamponade: rarely w/ classic presentation of low BP, muffled sounds and JVD. –Echocardiography, pericardiocentisis
Pericarditis/ Uremic Pericarditis: Uremic more common=75% Fluid overload, abnl platelet function, ↑ fibrinolytic and inflammatory cell activity Friction Rubs= louder, palpable, persist after metabolic abnormality resolved BUN always>60 mg/dl Absent EKG changes
Dialysis related percarditis: recurrent, most common type during dialysis. More common adhesions and fluid loculations ESRD w/ pericarditis= 8% Tx w/ dialysis Avg survival without dialysis= 1 month
Hematologic Complications: Anemia: low erythropoietin, blood loss from dialysis, ↓ RBC survival times –Normocytic, normochromic –Hct without tx. –Tx=erythropoietin
Bleeding diathesis: ↑ risk of GI bleed, subdural. – Can try tx with desmopressin Immunologic deficiency: leukocyte chemotaxis and phagocytosis decreased in uremic state. – Dialysis does not help immune function.
GI complications: Anorexia, nausea, vomiting=common in uremia Increased GI bleeding Chronic constipation Ascites from portal HTN, polycystic liver ds., fluid overload.
Renal Bone Disease: Systemic calcification; ↓ GFR=↑ serum phosphate levels. – Pseudogout, metastatic calcification of tissues, vessels. –Tx=low Ca dialysate and phosphate-binding gels
Hyperparathyroidism (Osteitis Fibrosa Cystica); –↓ ionized Ca=↑ PTH= high bone turnover, weak bones. –Tx=phosphate binding gels, Vit D3 replacement, subtotal parathyroidectomy
Osteomalacia; defect in bone calcification d/t Vit.D3 deficiency and aluminum intoxication Weakened bones, muscle pains, weakness Low PTH, ow to normal alkaline phosphate levels, ↑ serum aluminum Tx= desferrioxamine
Β2-Microglobulin amyloidosis: Pts >50 yrs old, on dialysis >10 yrs Amyloid deposits in GI tract, bones, joints. Complications; GI perfs, bone fx’s, carpal tunnel, rotator cuff tears. Pts w/ amyloidosis have ↑ mortality rates
Hemodialysis Uses ultrafiltration and clearance to replace nephron. Solute removal depends on filter pore size and concentration gradient Heparin units typically used Sessions 3-4 hrs.
Thrombosis and Stenosis of Access: Most common complication Loss of bruit and thrill Stenosis / thrombosis: not Emergencies= tx w/in 24 hours.
Vascular Access Infections: 2-5% of fistulas, 10% of grafts Often signs of sepsis, fever, Hypotension, ↑ WBC Erythema, swelling, discharge at site often missing. Staph Aureus #1, gram neg #2 Vanc is drug of choice, usually add Gent.
Hemorrhage: d/t aneurysm, anastomosis rupture or over anticoagulation. Direct pressure Protamine mg or 0.01 mg/unit hep. Consult surgery or nephrology
Vascular access aneurysms: Repeated punctures Bulging in wall Rarely rupture True aneurysms very rare; 4% of fistulas
Vascular access pseudoaneurysm: Subcutaneous extravasation of blood Present w/ bleeding & infection at site
Vascular insufficiency: distal to access “steal syndrome” Preferential shunting of blood to low pressure venous side s/s exercise pain, non-healing ulcers, cool pulseless digits Dx w/ doppler or angiography
High-output heart failure: When 20% of cardiac output diverted through access Branham sign: drop in HR after temporary access occlusion Doppler to measure access flow rate Surgical banding of access is Tx.
Complications During Hemodialysis 1. Hypotension: Most frequent, 10-20% of treatments Dialysis can remove up to 2 L/hr. Cardiac compensation limited d/t ↓ diastolic function common in ESRD Abnormalities in vascular tone; sepsis, anit HTN meds, ↑ nitric oxide
Early hypotension: pre-existing hypovolemia Peridialysis losses; starts HD below dry weight; d/t sepsis, GI bleed, vomiting, diarrhea, decreased salt/water intake Intradialytic blood loss from tubing/dialyzer leads Hypotension at end of dialysis: excessive removal, cardiac or pericardial disease.
Intradialytic hypotension: N/V/anxiety, ortho hypotension, tachycardia, dizzy, syncope. Tx.; stop HD, Trendelenburg. Salt, broth by mouth, NS cc. IV. If these fail look for other causes than excessive fluid removal
2. Dialysis disequilibrium: End of dialysis N/V, HTN...progress to coma, seizure and death d/t cerebral edema after large solute clearance in HD Tx. Stop HD, administer Mannitol IV.
3. Air Embolism: s/s: dyspnea, chest tightness, unconscious, full cardiac arrest. Cyanosis, churning sound in heart from bubbles Clamp venous blood line, place supine Other Tx’s: percutaneous aspiration from R ventricle, IV steroids, full heparinization, hyperbaric O2 treatment
4. Electrolyte abnormalities: ↑ Ca, ↑Mg N/V, HA, burning skin, weakness, lethargy HTN 5. Hypoglycemia
Evaluation of HD Patients Dialysis schedule Dry weight Length of dialysis Inspect access site; erythema, swelling, tender, discharge. Peripheral edema, HJR, JVD not always CHF Murmurs; high flow d/t anemia?
Peritoneal Dialysis Peritoneal membrane= blood-dialysate interface Can be done acutely, chronically(continuous)=4 times/day, or multiple exchanges at night while sleeping.
Complications Peritonitis #1 Mortality % Fever, abd pain, rebound tender Dialysate fluid for cell count, Gram stain, culture Staph epidermidis 40%, S. aureus 10%, Strep species 15-20%, gram neg bacteria 15-20%, anaerobic bacteria 5%, fungi 5%.
Empiric antibiotic therapy Add to dialysate Parenteral administration not needed Rapid exchanges of fluid lavage to wash out inflammatory cells First gen Ceph Vanc if pen allergic Can add Gent
Infections around PD catheter site: Pain, erythema, swelling, discharge. S. aureus, Pseudomonas aeruginosa Empiric w/ first generation Ceph or Cipro Outpatient therapy with f/u at CAPD center next day
Overview Evaluating PD Patient Type and frequency of dialysis Date of last episode of peritonitis Frequency of relapse infections Baseline weight Focus on abdomen and catheter tunnel
Questions: 1. T/F Peripheral Neuropathy, “stocking and glove pattern”, is rarely seen in ESRD pts on dialysis. 2. T/F ESRD patients carry the same cardiovascular risk as general population. 3. T/F Troponins are commonly significantly elevated in patients on regular dialysis and cannot be trusted as cardiac marker.
4. #1 cause of dialysis access site infections… –A. klebsiella –B. staph aureus –C. strep species –D. E. coli
5. #1 complication during dialysis sessions is …. –A. hypotension –B. fever –C. CHF –D. cough Answers: false (seen in 50%), false(inc risk), false, B, A.