Effects of Dexmedetomidine Premedication on Geriatric Patients With Chronic Renal Failure Undergoing Hip Surgery
Condition: Chronic Renal Failure; Hip Fracture
MeSH terms: Renal Insufficiency; Kidney Failure, Chronic; Renal Insufficiency, Chronic; Fractures, Bone; Hip Fractures
Study type: Interventional
Phase: Phase 3

Summary: 
      Geriatric patients (age ≥ 65 years) undergo surgery for hip fractures that develops due to
      osteoporosis and falls. Dialysis-dependent chronic kidney disease is associated with an
      increased risk of cardiovascular comorbidity. Elective or urgent surgical operations may be
      required for geriatric patients with end stage renal disease. These patients have severe
      comorbidities, fluid, electrolyte disturbances and drug metabolism abnormalities during the
      perioperative period. For this reasons a careful anesthesia plan should be planned and
      performed. Spinal anesthesia can be used for hip fracture surgery at geriatric patients with
      chronic renal failure. Anterograde femoral intramedullary nailing can be performed in supine
      position with a fracture table. Intraoperative sedation might be necessary for patients under
      regional anesthesia on traction table. Dexmedetomidine is an alpha 2 receptor agonist that is
      being used as an agent for its sedative and adjuvant analgesic effects.

      The aim of this study is to evaluate the effects of dexmedetomidine premedication on
      geriatric patients with end stage renal disease, who will be undergoing a surgical operation
      for hip fracture under spinal anesthesia with hyperbaric bupivacaine and BIS (Bispectral
      Index) guided sedation with intraoperative propofol infusion.
    

Detailed description: 
      Patients will be randomized into two separate groups.Group Dexmedetomidine (Group D):
      Midazolam 0.02 mg/kg + 0.5 μg/kg/10 min dexmedetomidine infusion for premedication; Spinal
      block (Hyperbaric bupivacaine 0.5% 12.5 mg) (n=30) Group Control (Group C): Midazolam 0.02
      mg/kg + saline infusion for premedication; Spinal block (Hyperbaric bupivacaine 0.5% 12.5mg)
      (n=30)

      In this randomized double-blinded study, drugs will be prepared by an anesthesia technician
      who is not part of the study. The patients will be monitored with a pulse-oxymeter, 5-channel
      ECG, noninvasive blood pressure and BIS at the preoperative preparation room. BIS monitoring
      electrodes will be placed on the forehead of the patient. Study drugs will be administered to
      the patient by another anesthesiologist who is also not taking part in the study at the
      preparation room preoperatively. Dexmedetomidine (0.5 μg/kg) in 20 ml saline will be
      administered in 10 minutes, with an infusion pump. An equivalent volume of saline solution
      will be given to the control group with same method. Baseline, 1., 3., 5., 10., minute BIS
      SpO2, systolic, diastolic and mean arteriel pressure values will be recorded. At this period
      500 ml of 0.9% NaCl will be infused. The patient will then be transported to the operating
      room with the supervision of this anesthesiologist. The intraoperative and postoperative
      follow-up of the patients will be performed by another anesthesiologist who has been blinded
      to the study drugs as well as the group distribution. Routine anesthesia monitoring will be
      performed with pulse-oxymeter, 5-lead ECG, noninvasive blood pressure measurement, pulse
      oxymetry and BIS. Before induction of the spinal block basal systolic, diastolic and mean
      blood pressures, heart rate, peripheral oxygen saturation and BIS values will be recorded.
      Lumbar puncture will be performed in lateral decubitis position with a Quincke 27 gauge
      spinal needle at the L3-L4 interspaces using the midline approach. Patients will be promptly
      rotated supine position after block induction. Induction of the spinal block will be accepted
      as 0 for all intraoperative data recordings. Systolic, diastolic and mean blood pressures,
      heart rate, peripheral oxygen saturation and BIS values will be recorded at 1.,3. 5. minutes
      and every 5 minutes for the first hour and following that every 15 minutes during surgery.

      Hypotension will be described as a drop off in systolic pressure by greater then 25% from the
      baseline or in case systolic blood pressure decreases below 90 mm Hg, 5 mg ephedrine will be
      administered intravenously and the rate of crystalloid infusion will be increased.

      The sensorial block level and the motor block level will be tested with the pinprick test and
      Bromage scale (Bromage Scale; 0: No motor block: full flexion of knee and foot, 1: Inability
      to raise extended leg. Just able to move knee, 2: Inability to flex knee. Able to move foot
      only, 3: Inability to flex ankle joint. Unable to move foot or knee), respectively. Propofol
      infusion will be started in all patients at a dose of 50 mcg/kg/min after the level of block
      arises to T10 dermatome level. Target BIS values will be between 70 and 80. Infusion rate
      will be titrate to provide the targeted BIS levels.The time when BIS < 80 will be recorded.
      In case BIS<70, propofol infusion rate will be reduced. ''Observer's assessment of
      alertness/sedation (OAA/S)'' scale (OAAS score 5-awake and responds readily to name spoken in
      normal tone, OAAS score 4-lethargic responses to name in normal tone, OAAS score 3-responds
      only after name is called loudly and/or repeatedly, OAAS score 2-responds only after name
      called loudly and mild shaking, OAAS score 1-does not respond when name is called loudly and
      mild shaking or prodding, OAAS score 0-does not respond to noxious stimulation) will be used
      for evaluating the level of sedation, with a target of OAA/S ≤ 5. OAA/S scores will be
      registered at the same time points. Propofol infusion will be ended at the beginning of skin
      suturing, and BIS>90 time will be recorded.

      Patients will be monitored at the postoperative care unit and all monitoring parameters (MAP,
      SAP, DAP, BIS, OASS) will be registered at every 5 minutes for one hour. Criteria for
      transferring the ward are BIS>90, OAA/S=5, Bromage=0-1 Duration of the surgery, the amount of
      bleeding, vasoactive drug need, the time necessary to reach the targeted level of sedation
      (BIS≤80), the amount of propofol infusion, propofol dose required for targeted BIS levels and
      the total propofol consumption recovery time (BIS>90) first analgesic requirement time (VAS:
      Visual Analogue Scale;0=no pain, 10=worst pain possible,VAS≥3) and the complications will be
      recorded. Side effects and possible complications during the intraoperative period and the
      postoperative follow-up include: hypotension (SBP<90 mmHg), bradycardia (CR < 60/min),
      hypoxia (SpO2≤ 94 %), nausea, vomiting, and respiratory depression will be recorded and the
      necessary medical interventions will be administered.
    

Intervention name(s): dexmedetomidine infusion for premedication; Midazolam; saline infusion; Spinal block with hyperbaric bupivacaine 0.5% 12.5 mg
Intervention type(s): Drug; Drug; Drug; Drug
Intervention description(s): Group Dexmedetomidine (Group D): Midazolam 0.02 mg/kg + 0.5 μg/kg/10 min dexmedetomidine infusion for premedication; Spinal block (Hyperbaric bupivacaine 0.5% 12.5 mg) (n=30); intravenous Midazolam 0.02 mg/kg for premedication; Saline infusion to facilitate blinding; Hyperbaric bupivacaine injection for spinal block
Other intervention name(s): Precedex 200mcg/2ml; 121/87; Hospira İnc., Rocky Mount, NC 27801 USA; Demizolam; Dem İlaç San. ve Tic AŞ.; 0.9% sodium chloride solution; Marcaine Spinal Heavy 0.5%; Astra Zeneca; 21.01.2000-194/86
Intervention MeSH terms: Midazolam; Dexmedetomidine; Bupivacaine
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Keywords: Renal failure,; hip fracture,; spinal anesthesia,; dexmedetomidine; patient