Intrathecal Administration of Levobupivacaine and Opioids in Elderly
Condition: Adverse Reaction to Spinal Anesthetic
Study type: Interventional

Summary: 
      To find the optimal dose and combination of small dose of Levobupivacaine (LB) coadministered
      intrathecally with Fentanyl (F) or Sufentanil (S) with the highest probability for not
      developing hypotension and the lowest opioid side effect that would be sufficient to achieve
      and maintain a sensory block to the tenth thoracic dermatoma (T10) in elderly patients for
      surgery lasting > 45 minutes as compared with large dose of Levobupivacaine alone.
    

Detailed description: 
      Hypotension and bradycardia are the most common adverse hemodynamic effects associated with
      spinal anesthesia, with particular frequency among the elderly. These complications are more
      hazardous in the elderly because they may have decreased physiological reserves and
      compromised blood supply to various vital organs. Hypotension is mainly related to the spinal
      anesthesia block height. One approach to improve hemodynamic stability is to use smaller
      doses of local anesthetic (< 10 mg of Levobupivacaine) to limit the distribution of local
      anesthetic within the subarachnoid space and hence to limit the block height. However, a
      smaller dose of local anesthetic may increase the incidence of inadequate level of sensory
      anesthesia for the anticipated surgery as compared with larger doses (> 10 mg of
      Levobupivacaine). Another concern about smaller dose of local anesthetic is the inadequate
      duration of sensory anesthesia. Therefore, small dose of local anesthetic need to be combined
      with opioids (Fentanyl or Sufentanil). However, intrathecal opioids are associated with
      several side effects such as pruritis, nausea, vomiting, shivering and respiratory
      depression. This will be the first comparative study of two small doses of Levobupivacaine (6
      and 8 mg) combined using intrathecal Fentanyl (F, 25 and 35 mcg) or Sufentanil (S, 5 and 7
      mcg) compared with large dose of Levobupivacaine alone (12 mg) in spinal anesthesia. The
      study will be conducted to assess the impact of a 10 independent variables (dose and
      combination of Levobupivacaine with Fentanyl or Sufentanil, age, basal systolic blood
      pressure (SBP), basal mean arterial pressure (MAP), time to lowest spinal SBP, upper limit of
      sensory block (dermatome level), time intervals of sensory recovery for two consecutive
      dermatome level (two-segment regression), time intervals of sensory recovery to the twelfth
      thoracic dermatoma (T12 regression), time intervals of sensory recovery to the first sacral
      dermatoma (S1 regression) and Body Mass Index) on the likelihood of not developing
      hypotension after intrathecal injection. The goal of the study is to find an optimal dose and
      combination of Levobupivacaine and Fentanyl or Sufentanil with the highest probability of not
      developing the hypotension as well as with the lowest opioid side effect that would be potent
      enough in achieving and maintaining a sensory block at T10 level for surgery lasting more
      than 45 minutes in elderly patients.
    

Intervention name(s): The impact of 10 independent variables on the likelihood of not developing hypotension after intrathecal injection.
Intervention type(s): Drug
Intervention description(s): The study will be conducted to assess the impact of a 10 independent variables (dose and combination of Levobupivacaine with Fentanyl or Sufentanil, age, basal systolic blood pressure (SBP), basal mean arterial pressure (MAP), time to lowest spinal SBP, upper limit of sensory block (dermatoma level), time intervals of sensory recovery for two consecutive dermatoma level (two-segment regression), time intervals of sensory recovery to the twelfth thoracic dermatoma (T12 regression), time intervals of sensory recovery to the first sacral dermatoma (S1 regression) and Body Mass Index) on the likelihood of not developing hypotension after intrathecal injection.
Other intervention name(s): levobupivacaine
Intervention MeSH terms: Levobupivacaine
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Treatment