None listed
Conditions
Brief summary
Dexmedetomidine is a drug that is commonly used on Intensive Care Units across the world in patients requiring sedation as part of their medical treatment. This research aims to see if this drug is protecting or causing harm to the kidneys. We will do this by using very sensitive techniques that detect kidney function, which are not used in routine clinical practice. There have been a few studies looking at this drug in the past, mainly with people undergoing heart operations. There have also been some studies looking at animals being given this drug for sedation. The results of these have been mixed, meaning that it is unclear what the true effect is of dexmedetomidine on the kidneys. This study hopes to look at a small number of patients who are already receiving this drug as part of their treatment and see what happens to their kidney function after they start receiving it.
Interventions
Patients in intensive care receiving dexmedetomidine sedation are observed for a 24 hour period. Arterial blood will be drawn from an existing arterial line and urine will be collected from an existing urinary catheter. This means there will not be any discomfort or inconvenience for the patient. The following samples will be collected:
• 1 ml blood in a safePICO Aspirator syringe
o for pH, pO2, pCO2 & lactate
• 4 ml blood in a lithium-heparin tube
o for metanephrines
• 4 ml blood in an EDTA
Patients in intensive care receiving dexmedetomidine sedation are observed for a 24 hour period. Arterial blood will be drawn from an existing arterial line and urine will be collected from an existing urinary catheter. This means there will not be any discomfort or inconvenience for the patient. The following samples will be collected: • 1 ml blood in a safePICO Aspirator syringe o for pH, pO2, pCO2 & lactate • 4 ml blood in a lithium-heparin tube o for metanephrines • 4 ml blood in an EDTA tube o for renin • 2 ml blood in an EGTA tube containing glutathione o for plasma noradrenaline • 3 ml blood in an EDTA tube o for serum cystatin C & plasma cytokines (tumour necrosis factor alpha, interleukin 6 & interleukin 10) • 2 ml blood in a tube containing EDTA, reduced glutathione and butylated hydroxytoluene o for plasma free F2-isoprostanes (non-esterified) • 2 ml urine in a sterile container o for neutrophil gelatinase-associated lipocalin and F2-isoprostanes These samples will be collected prior to the patient receiving dexmedetomidine and at 2, 4, 8 and 24 hours after dexmedetomidine infusion has been started. The total blood volume collected during the study will be 80 ml and the total urine volume will be 10 ml. We will also record the sodium, potassium and creatinine levels at the start and end of the study that are done daily on the ICU as part of routine care. The continuous assessment of urinary oxygenation will be measured using an oxygen sensor probe developed by Oxford Optronix Ltd., 19-21 East Central, 127 Olympic Avenue, Milton Park, Abingdon, Oxfordshire OX14 4SA, United Kingdom. The sensor is inserted into the urinary catheter so that it remains within the catheter and does not exit the tip. This aims to avoid incorrect measurement of bladder wall oxygen tension instead of true urinary oxygen tension, and also means there will not be any discomfort for the patient. This would provide continuous measurements of the urinary oxygenation. This will be used as a surrogate marker of medullary tissue pO2 and thus, renal oxygenation.
Sponsors
The Royal Melbourne Hospital ICU
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Patients will be eligible for participation if their treating doctor was already intending to start them on this treatment (dexmedetomidine) for an existing clinical indication.
Exclusion criteria
Patients will be excluded if aged less than 18 years, pregnant, or they have acute or chronic end stage kidney failure and are receiving renal replacement therapy.
Outcome results
None listed