Evaluation Of The Degree Of Kidney Injury in Children With Hypovolemic Shock

Acute kidney injury is a syndrome characterised by the rapid loss of the kidney's excretory function and is typically diagnosed by the accumulation of end products of nitrogen metabolism (urea and creatinine) or decreased urine output, or both. It is the clinical manifestation of several disorders that affect the kidney acutely. Acute kidney injury is common in hospital patients and very common in critically ill patients. In these patients, it is most often secondary to extrarenal events.. In low-income and middle-income countries, infections and hypovolaemic shock are the predominant causes of AKI. In high-income countries, AKI mostly occurs in elderly patients who are in hospital, and is related to sepsis, drugs or invasive procedures. Infection and trauma-related AKI and AKD are frequent in all regions.

There are numerous potential causes of AKI, mainly related to a focal mismatch between oxygen and nutrient delivery (because of impaired microcirculation) to the nephrons and increased energy demands (due to cellular stress).

The prerenal form of AKI is due to any cause of reduced blood flow to the kidney. This may be part of systemic hypoperfusion resulting from hypovolemia or due to selective hypoperfusion of the kidneys, such as

• Hypovolemia: hemorrhage, severe burns, and gastrointestinal fluid losses such as diarrhea, vomiting, and high ostomy output.
• Hypotension from systemic vasodilation: septic shock, anaphylaxis, anesthesia administration.
• Glomerular efferent arteriolar vasodilation (causing intraglomerular hypotension): ACE inhibitors, angiotensin receptor blockers.

Diagnosis

• Increase in serum creatinine by 0.3 mg/dL or more (26.5 μmol/L or more) within 48 hours And other diagnostic criteria according to the stage Shock is the state of insufficient blood flow to the tissues of the body as a result of problems with the circulatory system.[5][6]Initial symptoms of shock may include weakness, fast heart rate, fast breathing, sweating, anxiety, and increased thirst Shock is divided into four main types based on the underlying cause: hypovolemic, cardiogenic, obstructive, and distributive shock.Hypovolemic shock, also known as low volume shock, may be from bleeding, diarrhea, or vomiting.

One of most common complication of shock is acute kidney injury due to decrease perfusion to kidney which can improved once shock improved

Management :

Aggressive intravenous fluids are recommended in most types of shock (e.g. 1-2 liter normal saline bolus over 10 minutes or 20 mL/kg in a child) which is usually instituted as the person is being further evaluated.[7] Colloids and crystalloids appear to be equally effective with respect to outcomes.,[8] Balanced crystalloids and normal saline also appear to be equally effective in critically ill patients.[9] If the person remains in shock after initial resuscitation, packed red blood cells should be administered to keep the hemoglobin greater than 100 g/L.

Some AKI patients tend to develop volume overload, which should be corrected as early as possible to avoid pulmonary and cardiac complications. Euvolemic state can be achieved with the help of diuretics, which is a cornerstone in managing such patients. Usually, high doses of IV furosemide are needed to correct volume overload in AKI patients; however, it plays no role in converting oliguric AKI to non-oliguric AKI.

In some cases, short-term renal replacement therapy is needed for AKI until the kidney function recovers. Some indications for RRT are severe and non-responsive hyperkalaemia, uremic pericarditis, and pulmonary oedema where the patient is prone to develop multiple electrolyte and acid-base abnormalities as well as fluid overload.

Dialysis in this setting is usually performed through a temporary venous catheter when required. Continuous renal replacement therapy can also be utilized in patients who cannot tolerate haemodialysis due to hypotension. It is a much slower, continuous type of dialysis. . Metabolic acidosis is one such instance where systemic administration of citrate or bicarbonate is often required to maintain a suitable blood pH. The requirement for renal replacement therapy should be re-evaluated daily. Renal replacement therapy is usually required for short periods, ranging from a few days to a few weeks; however, some cases can take months to recover and may require intermittent RRT support.