Combined lowdose spinalepidural anesthesia versus singleshot spinal anesthesia for elective cesarean

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Combined low-dose spinal-epidural anesthesia
versussingle-shot spinal anesthesia for elective
cesarean delivery

• International Journal of Obstetric Anesthesia
  (2006) 15, 1317
• R3 ???

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INTRODUCTION

• Spinal anesthesia has been more popular for
  cesarean delivery because it offers a
  rapid-onset, profound, reliable block.
• Large doses of bupivacaine for fear of inadequate
  analgesia or visceral pain during surgery
• Large doses
• ?may induce higher sensory block than
• expected
• ?extensive sympathetic block, often induces
• hypotension, nausea, vomiting and
  dizziness.

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INTRODUCTION

• The use of left uterine displacement, fluid
  preloading and prophylactic ephedrine.
• Low-dose combinations of local anesthetic with
  opioid
• Combined spinal-epidural (CSE) technique
• Intrathecal doses of local anesthetic to be
  greatly reduced? associated complications.

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INTRODUCTION

• Intrathecal bupivacaine 6 mg with opioid
  epidural injection of 0.25 bupivacaine 10 mL
• Single-shot spinal anesthesia using bupivacaine 9
  mg with opioid
• Cesarean delivery feasibility and incidences of
  side effects such as hypotension and nausea.

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METHODS

• A prospective randomized and double blinded
  study.
• 102 women at term pregnancy (P36 weeks) scheduled
  for elective cesarean delivery
• The patients were allocated to receive either CSE
  (n 52) or spinal anesthesia (n 50) using a
  computer-generated randomization list.

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METHODS

• Excluded
• ? Parturients with pregnancy-induced
• hypertension
• ? multiple pregnancies
• ? placenta previa
• ? cardiac diseases
• ? contraindications to regional anesthesia

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METHODS

• All parturients were rapidly infused with 20
  mL/kg of L/R solution.
• Oxygen was administered ? 3 L/min through a nasal
  cannula.
• Electrocardiogram, noninvasive blood pressure and
  pulse oximetry were monitored and baseline values
  recorded

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METHODS

• Right lateral position, L3-4 interspace, midline
  approach.
• For patients in the CSE group, an 18-gauge Tuohy
  needle was introduced using loss of resistance to
  air
• Dural puncture with a 27-gauge Sprotte needle
  using the needle-through needle technique..

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METHODS

• After confirming with aspiration CSF , 0.5
  hyperbaric bupivacaine 6 mg mixed with fentanyl
  20µg was administered.
• A 20-gauge epidural catheter was inserted through
  the epidural needle 3-4 cm into the epidural
  space and the catheter was firmly fixed

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METHODS

• Patients were then placed in the supine position
  with left uterine displacement using an airbag
  under the right hip
• 5 min after the intrathecal injection, 0.25
  bupivacaine 10 mL was given through the epidural
  catheter.

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METHODS

• Patients in the spinal group were given 9 mg of
  0.5 hyperbaric bupivacaine with fentanyl 20µg
  through a 27-gauge Sprotte needle via a 20-gauge
  introducer
• A sham epidural catheter as used in the CSE group
  was applied to the patients back
• Patients were turned supine with left uterine
  displacement.

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METHODS

• 5 min after the intrathecal injection, 0.25
  bupivacaine 10 mL was administered into the sham
  catheter and was soaked up by gauze
• The completion of the intrathecal injection was
  taken as time 0 min in both groups.

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METHODS

• The investigator, who was not aware of the
  anesthetic technique allocated to each patient,
  entered the operating room immediately and
  recorded all variables.
• Maternal blood pressure was recorded every minute
  for 10 min after the intrathecal injection, at
  2-min intervals for the next 10 min and at 5-min
  intervals thereafter

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METHODS

• Hypotension 20 or more fall below the
  pre-induction level or systolic pressure below 95
  mmHg, which was treated immediately with
  ephedrine 5 mg i.v. and repeated whenever
  necessary.
• Sensory and motor block were tested 5, 10, 15,
  20, 30, 60, 90 and 120 min after induction.

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METHODS

• Motor block was assessed using a modified Bromage
  scale
• BS 0 no block
• BS 1 weak or absent hip flexion, able to
• move knees and ankles
• BS 2 unable to move hips or knees,
• able to move ankles
• BS 3 unable to move any joint

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METHODS

• Intraoperative pain, gt30 on the visual analogue
  scale (VAS) of 0-100, was to be treated with
  fentanyl 50 µg i.v. once or twice.
• Patients not responding to two fentanyl
  injections were to be excluded from this study

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METHODS

• Adverse effects nausea and vomiting, shivering,
  pruritus and dizziness after induction of
  anesthesia were checked every 10 min throughout
  the operation.
• The times required for sensory recovery to T10,
  motor recovery to BS 0, and the onset of
  postoperative pain were recorded in the
  postanesthetic care unit (PACU).

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RESULTS

• Among 52 patients in the CSE group, there were
  technical failures in two patients

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RESULTS
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RESULTS
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RESULTS
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RESULTS
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DISCUSSIONS

• Combined low-dose spinal-epidural anesthesia
• ? offered better hemodynamic stability
• ? showed faster motor recovery in the
• post-OP period
• ? did not elevate the sensory block levels.

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DISCUSSIONS

• A smaller spinal dose used for CSE elevated the
  sensory block level more slowly, and hypotension
  and nausea occurred less frequently in this group
• The standard CSE technique mainly uses
• ? inadequate block during surgery
• ? postoperative pain management.

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DISCUSSIONS

• There are two steps before obtaining surgical
  anesthesia1) low-dose spinal anesthetic in the
  sitting position aiming at a low thoracic block
• 2) titration of sensory block to T4 by the
  use of fractionated epidural injections
• This two-stage sequential technique was designed
  to avoid precipitous hypotension from a
  single-shot spinal ? delay surgical time
• Rawal N, Schollin J, Wesstrom G. Epidural versus
  combined spinal epidural block for cesarean
  section. Acta Anaesthesiol Scand 1988 32 6166.

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DISCUSSIONS

• Modified sequential CSE technique using the
  lateral position and 5 mg of bupivacaine followed
  by epidural lidocaine titrated to achieve an
  adequate block, was also demonstrated to reduce
  the incidence and severity of hypotension.
• Fan S Z, Susetio L, Wang Y P, Cheng Y J, Liu C C.
  Low dose of intrathecal hyperbaric bupivacaine
  combined with epidural lidocaine for cesarean
  sectiona balance block technique. Anesth Analg
  1994 78 474477.

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DISCUSSIONS

• In the CSE technique, an epidural injection,
  whether of local anesthetic or simply of saline,
  has been shown to extend the pre-existing spinal
  block.
• A volume effect from epidural saline compressing
  the dural sac results in rostral migration of
  freshly administered spinal anesthetic.

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DISCUSSIONS

• 8 mg of hyperbaric bupivacaine, the maximum
  sensory height was reached at 8.9 min after the
  subarachnoid injection.
• We found that 10 mL of both 0.25 bupivacaine and
  saline administered 10 min after the subarachnoid
  injection extended the sensory block level by one
  segment, but only the local anesthetic sustained
  the level long enough to complete the operation
• Choi D H, Park N K, Cho H S, Hahm T S, Chung I S.
  Effects of epidural injection on spinal block
  during combined spinal and epidural anesthesia
  for cesarean delivery. Reg Anesth Pain Med 2000
  25 591595

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DISCUSSIONS

• The time, 5 min, was chosen because we wanted to
  give the epidural injection before the
  subarachnoid block had reached its peak height
• time was needed to confirm successful spinal
  block and also to insert and fix the epidural
  catheter and reposition the patient.

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DISCUSSIONS

• A recent study using epidural saline for the
  volume effect also demonstrated faster motor
  recovery (136 vs. 73 min, P lt 0.05) than in the
  single-shot spinal group.
• The volume effect using saline can increase the
  spread of a small intrathecal dose to equal that
  of a bigger one, the duration tends to be
  proportionately reduced.
• Lew E, Yeo S W, Thomas E. Combined
  spinal-epidural anesthesia using epidural volume
  extension leads to faster motor recovery after
  elective cesarean delivery a prospective,
  randomized, double-blind study. Anesth Analg
  2004 98 810814.

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DISCUSSIONS

• The use of prophylactic epidural bupivacaine
  rather than saline reduces the need for
  therapeutic epidural supplementation during the
  subsequent surgery.
• Routinely combining main spinal and supporting
  epidural anesthesia before surgery in our study
  did not delay onset.

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DISCUSSIONS

• We did not include a control group of patients
  given the spinal dose of 6 mg of bupivacaine and
  fentanyl 20 µg alone
• Subarachnoid injection of 6 mg of bupivacaine and
  fentanyl 20 µg was not sufficient to provide
  surgical anesthesia for cesarean delivery.

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DISCUSSIONS

• We did not observe pruritus as often as other
  studies.
• Because intrathecal fentanyl usually induces only
  mild pruritus and the presence of pruritus was
  not actively sought, but recorded only when the
  patients complained of it.

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DISCUSSIONS

• A routine timely epidural supplementation of 10
  mL of 0.25 bupivacaine via the CSE technique
• ? provides excellent surgical anesthesia for
  cesarean delivery after otherwise insufficient
  low-dose spinal anesthesia
• ? reduces the intrathecal dose requirement of
  bupivacaine resulting in low frequency of
  hypotension and nausea and quicker motor recovery.

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