Chronic kidney disease (CKD) is the progressive, irreversible deterioration of renal function that results from a wide variety of diseases. Patients having a glomerular filtration rate (GFR) less than 60 mL/min/1.73 m2 for more than 3 months are defined as having CKD. This disease, however, affects not only kidneys per se but has widespread pathophysiological manifestations affecting multiple organ systems, which play an important role in the anesthetic management when such a patient is posted for surgery (Table 18.1).
Hyperkalemia: This is caused by the inability of kidneys to excrete potassium, the majority of which is dependent on renal excretion. It may be aggravated by factors such as drugs (beta-blockers, K+ sparing diuretics, angiotensin-converting enzyme [ACE] inhibitors) and extracellular acidosis.
Anesthetic implication: All patients should undergo preoperative estimation of serum potassium levels, and if elevated, then ECG should be done. Succinylcholine should be avoided if serum potassium is > 5.5 mEq/L.
Chronic metabolic acidosis: This occurs due to loss of ability to secrete protons and buffers in exchange for bicarbonate. Initially, it is of normal anion gap variety but progresses to high-anion gap variety in advanced renal failure.
Anesthetic implications: Hypocalcemia can cause laryngospasm and hypotension. Therefore, symptomatic hypocalcemia must be treated before surgery. Avoid hyperventilation and alkalosis during the perioperative course, which can aggravate hypocalcemia.
Accelerated atherosclerosis and ischaemic heart disease: This is the result of decreased plasma triglyceride clearance, hypertension, and fluid overload, causing left ventricular hypertrophy and failure.
Anesthetic implications: Cardiovascular disease (CVD) is a major cause of perioperative morbidity and mortality in CKD patients, necessitating the need for detailed cardiovascular evaluation and optimization preoperatively. Thrombosis of central veins may make cannulation difficult.
Anesthetic implications: CKD patients should undergo platelet count, standard coagulation tests, and further qualitative analysis, if required, especially if regional anesthesia is planned. There may be increased bleeding tendency intraoperatively, and it is managed with transfusion of cryoprecipitate, platelets, or desmopressin. Heparin should be avoided during preoperative dialysis to lessen intraoperative bleeding.