Perineural Versus IV Dexmedetomidine as Adjuvant to Quadratus Lamborum Block for Pediatrics Undergoing Pyeloplasty
Condition: Pain, Postoperative
MeSH terms: Pain, Postoperative
Study type: Interventional
Phase: Early Phase 1

Summary: 
      this prospective parallel group double blinded study will be conducted over 50 pediatric
      patients ASA (American Association of Anesthesiologists) I and II between the age of 8-13
      years old,who will be scheduled for laparoscopic pyeloplasty.Patients will be randomly
      allocated into 2 study groups: Quadratus lamborum dexmedetomidine intravenous group(QD IV
      group) and Quadratus lamborum dexmedetomidine perineural group(QD PN group.Patients in both
      groups will receive quadratus lamborum block .In QD IV group a bolus of 0.5 ml/Kg bupivacaine
      0.25% in addition to 2ml normal saline will be injected then dexmedetomidine.1ml/kg loading
      dose will be given over 10 min followed by 0.5 ml/kg/h infusion maintenance dose till the end
      of surgery. In QD PN, patients will receive perineural dexmedetomidine of 1μ g/kg diluted to
      2 mL with 0.9% saline added to 0.5 ml/kg of 0.25% bupivacaine in addition to saline infusion
      1ml/kg IV loading dose followed by by 0.5 ml/kg/h infusion maintenance dose till the end of
      surgery.Time to first analgesic requirement ( primary outcome) , Wong-Baker FACES Pain Rating
      Scale scores will be recorded at 2, 6, 8,12, 18 and 24h postoperatively, the degree of
      sedation will be assessed by Ramsay sedation scores(fig.2)(9) at the same time points,
      hemo-dynamics as systolic and diastolic blood pressures and heart rates will be recorded at
      PACU discharge then 4 hourly, total dose of morphine consumption, , the length of hospital
      stay, incidence of postoperative complications as hypotension, bradycardia, vomiting,
      pruritis and respiratory depression
    

Detailed description: 
      this prospective parallel group double blinded study will be conducted over 50 pediatric
      patients ASA (American Association of Anesthesiologists) I and II between the age of 8-13
      years old, ASA physical status I and II, who will be scheduled for laparoscopic pyeloplasty
      and performed by the same surgical team. This study will be carried out at Ain Shams
      University hospitals. Written informed consent will be obtained from the parents. Exclusion
      criteria will include: History of developmental delay or mental retardation, parent refusal,
      history of allergic reactions to local anesthetics, rash or infection at the injection site,
      anatomical abnormality, bleeding disorders, history of cardiac, neurological, impaired renal
      function defined by s-creatinine >150 μmol/L and impaired hepatic function. Preanesthetic
      evaluation and routine investigations will be carried out on the night of surgery and
      patients shall be fasting for 6 hours. After an intravenous (IV) cannula (22G) is secured ,
      and midazolam 0.02 mg/kg iv will be administered to all patients before transfer to the
      operating room. Standard monitoring devices as ECG, Non- invasive blood pressure,
      nasopharyngeal temperature probe and pulse oximetry will be placed then baseline systolic and
      diastolic blood pressures and heart rate will be recorded. Induction of general anesthesia
      (GA) will be accomplished using propofol 1-2mg/kg, fentanyl will be administered
      intravenously at 1μg/kg, Intubation will be facilitated by atracurium (0.5 mg/kg) then an
      appropriately sized endotracheal tube will be placed.All patients will be mechanically
      ventilated with volume controlled mode with targeted EtCO2 (30-35 mmHg) and anesthesia will
      be maintained with 1.2% isoflurane in a mixture of 50% air and oxygen in all patients
      throughout the procedure which will be adjusted according to the adequacy of anesthesia.
      Intraoperative hypothermia will be prevented by warm intravenous fluids (15 ml/kg lactated
      ringer solution in the first hour then completed according to fluid chart) and warm mattress.

      A total of 50 patients will be randomly allocated into 2 study groups: Quadratus lamborum
      dexmedetomidine intravenous group(QD IV group) and Quadratus lamborum dexmedetomidine
      perineural group(QD PN group) using concealed envelope method, physicians assigned
      participants to interventions according to allocation: Patients in both groups will receive
      quadratus lamborum block on the same surgical side , first the patients will be placed in the
      lateral position then turned to supine position after completion of the block. Under aseptic
      conditions,a high-frequency linear probe (SonoSite HFL50x, 15- 6 MHz, 55-mm broadband linear
      array) will be placed on the lateral abdomen, between the costal margin and iliac crest. The
      three abdominal muscles, external oblique (EO), internal oblique (IO), and transversus
      abdominis muscle (TA), will be identified then the probe will be moved posteriorly and QL
      muscle (QLM) will visualized. A 22-G block needle (Stimuplex D, Braun, Hongo,
      Bunkyo-ku,Tokyo) will be oriented in plane, from anterior to posterior direction, and the
      needle tip will be positioned between the anterior border of QLM and its fascia: In QD IV
      group a bolus of 0.5 ml/Kg bupivacaine 0.25% in addition to 2ml normal saline will be
      injected then dexmedetomidine (precedex 200 micrograms per 2ml, Abbott laboratories, Abbott
      park, IL, USA) which will be prepared in concentration 1μg/ml. 1ml/kg loading dose will be
      given over 10 min followed by 0.5 ml/kg/h infusion maintenance dose till the end of surgery.
      In QD PN, patients will receive perineural dexmedetomidine of 1μ g/kg diluted to 2 mL with
      0.9% saline added to 0.5 ml/kg of 0.25% bupivacaine in addition to saline infusion 1ml/kg IV
      loading dose followed by by 0.5 ml/kg/h infusion maintenance dose till the end of surgery.
      Drug packs will be prepared before commencement of the study by a pharmacist unaware of the
      nature of the study, after 15 minutes of the block, surgical incision will be allowed but in
      case of conversion to open surgical procedure (laparotomy) patients will be excluded from the
      study.The average end-tidal isoflurane, total intraoperative fentanyl dose and incidence of
      intraoperative complications as hypotension, If the blood pressure dropped more than 30% of
      the baseline values, it will be managed by 10 ml/kg normal saline and ephedrine injection
      and/or bradycardia is defined as drop of heart rate more than 20% of the baseline values
      which will be managed by atropine 0.02mg/kg, all will be recorded. Inadequate analgesia is
      defined as more than 20% increase in mean blood pressure and heart rate after skin incision
      and during surgical procedure which will be managed by administration of 0.5 μg/kg fentanyl.
      At the end of surgical procedure, muscle relaxation will be reversed with neostigmine 50
      μg/kg and atropine sulfate 20 μg/kg. Patients will extubated and shifted to the
      post-anaesthesia care unit.

      The recovery time (The elapsed time for the patient to open his eyes upon command after
      discontinuation of Isoflurane) will be recorded. In postoperative anaesthesia care unit,
      postoperative monitoring of the hemodynamics will be undergone by a well trained nurse. when
      pain score >4 on Wong-Baker FACES Pain Rating Scale (8) (fig.1), patients will be given
      morphine 0.05 mg·kg-1 6 hourly and acetaminophen IV 15mg/kg 6 hourly will be administered by
      a physician blinded to the nature of the study as first and second rescue analgesics
      respectively. Time to first analgesic requirement ( primary outcome) , Wong-Baker FACES Pain
      Rating Scale scores will be recorded at 2, 6, 8,12, 18 and 24h postoperatively, the degree of
      sedation will be assessed by Ramsay sedation scores(fig.2)(9) at the same time points,
      hemo-dynamics as systolic and diastolic blood pressures and heart rates will be recorded at
      PACU discharge then 4 hourly, total dose of morphine consumption, , the length of hospital
      stay, incidence of postoperative complications as hypotension, bradycardia, vomiting,
      pruritis and respiratory depression, which is defined as respiratory rate less than 10
      breathes/min will be recorded. If the blood pressure dropped more than 30% 0f the baseline
      values, it will be managed by 10 ml/kg normal saline and ephedrine injection. Bradycardia is
      defined as drop of heart rate more than 20% of the baseline values. It will be managed by
      atropine 0.02mg/kg. Attacks of vomiting will be managed by ondansetron 0.1 mg/kg iv.
    

Intervention name(s): Quadratus lamborum dexmedetomidine intravenous; Quadratus lamborum dexmedetomidine perineural group(
Intervention type(s): Drug; Drug
Intervention description(s): Patients will receive quadratus lamborum block on the same surgical side then a bolus of 0.5 ml/Kg bupivacaine 0.25% in addition to 2ml normal saline will be injected then dexmedetomidine (precedex 200 micrograms per 2ml, Abbott laboratories, Abbott park, IL, USA) which will be prepared in concentration 1μg/ml. 1ml/kg loading dose will be given over 10 min followed by 0.5 ml/kg/h infusion maintenance dose till the end of surgery; Patients will receive quadratus lamborum block on the same surgical side then1μ g/kg diluted to 2 mL with 0.9% saline added to 0.5 ml/kg of 0.25% bupivacaine in addition to saline infusion 1ml/kg IV loading dose followed by by 0.5 ml/kg/h infusion maintenance dose till the end of surgery.
Other intervention name(s): (QD IV group); QD PN group
Intervention MeSH terms: Dexmedetomidine
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: randomisation by concealed envelope method
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Prevention
Keywords: quadratus - dexmedetomidine- bupivavaine- perineural