Segmental spinal is a boon for high risk patients for GA, for laproscopic surgeries, and maintains hemodynamic stability.

1. Change in Anesthesia
practices – Covid times
{Segmental Spinal}
DR. NEETA TANEJA
HOD, DEPT.
ANESTHESIA
SBAMI

2. Types of Cases done
► Lap cholecystectomy using isobaric levo-bupivacaine
0.5%(7.5mg) mixed with 20mics fentanyl at T9-10 level
► Total laproscopic hysterectomy mix of hyperbaric
bupiv(5mg)&isobaric bupiv(10mg) with 20mics fentanyl or in
some cases combined with epidural
► Total lap colectomy under CSE at T9-10 level
► Modified radical mastectomy using 7.5mg isobaric levo-
bupiv with 20mics fentanyl at T5 level

3. Thoracic spinal

4. Definition
► Segmental spinal is interchangeably used with
Thoracic spinal anesthesia
► In real sense,
“Blocking of the required dermatomes essential for the
proposed surgical procedure with very low effective
local anaesthetic drug”
► Necessitates dural puncture at high lumbar or mid to
lower thoracic levels
► Lower the dose, more likely, true segmental block

5. Perspective
► Was being used only in high risk morbid patients for
selective surgeries.
► Patients chosen for this technique need to be
evaluated carefully and the technique is to be
reserved for experienced clinicians
► it will establish itself as a routine procedure in day
care anaesthesia.

6. Types of cases
► Practically all the abdominal surgeries :
upper/lower,
major /minor, daycare/or not,
laparoscopic/open )
► Superficial thoracic surgeries,
► Breast surgeries are possible with
*Segmental spinal alone or
*CSE (combined spinal epidural). If thats not all then
*CSSA (continuous segmental spinal anaesthesia ) is also available.

7. History
In 1909 ,Thomas Jonessco proposed the
use of general spinal block for the
surgeries of head , neck and thorax ,
puncturing the SAS between 1st and
2nd thoracic vertebra and succeeded
to produce profound analgesia for the
head , neck and upper limbs. He also
punctured the SAS at mid thoracic and
lower thoracic levels for thoracic and
abdominal surgeries.

8. 1954
► Segmental spinal anesthesia of the lower thoracic was used.
► The information that there is substantially more space in the dorsal
subarachnoid space at thoracic level, might lead to potential application in
regional anesthesia.
► The thoracic spinal puncture at T10 showed a rapid onset of action, regardless
of baricity, decrease in the incidence of hypotension with faster recovery of the
blockade, with low incidence of paresthesia and no spinal cord injuries in 636
patients
► If it were possible to limit anesthesia to the operative field and to use
anesthetic agents in more diluted solutions and in smaller doses, certain
undesirable effects of spinal anesthesia could also be avoided. This is the
fundamental reason for using hemi anesthesia (posterior or unilateral) or
segmental spinal anesthesia.

9. 2006
► A new era of studies on segmental spinal anaesthesia,
J Van Zundert punctured SAS at T10 for laparoscopic cholecystectomy, to
anaesthetise a patient with severe obstructive lung disease.
Since then there have been many studies about segmental spinals exploring
its utility in many different surgical procedures like awake thoracoscopic /
thoracic surgeries , laparoscopic cholecystectomy , breast surgeries etc.

10. Intrathecal block can be performed in three distinct
zones
► 1st) a low zone, limited above by the 1st nerve segments of
the lumbar region, for operations on the lower limbs and
perineum;
► 2nd) a middle zone, limited above the 10th thoracic segment
(belly button), for operations on the lower abdomen and pelvis
and
► 3 rd) a high zone, limited above by the 4th thoracic segment
(nipple area), for operations on the abdomen upper and lower
thoracic.

11. ► Depending on the type of surgery, patients haemodynamic status and
associated co-morbid conditions the dose of local anaesthetic agent and
the site of injection along the neuraxis can be varied. For all abdominal
surgeries with a adequate dose ,thoracic spinal above T10 is hardly
required. Space between T10 and L1 is usually sufficient for all abdominal
procedures.
► On an average a dose of 7.5 to 10 mg (1.5 to 2ml) of
bupivaicaine/levobupivacaine with some additive ( fentanyl/clonidine)
works well for 90 to 120 mins. This dose is exactly half the amount
required when conventional spinal at lumber level to achieve a level of T3-
T4 is used.

12. ► segmental spinal anaesthesia means
► “ Blocking of the required dermatomes essential for the proposed
surgical procedure with very low effective local anaesthetic drug
dose.”
► This often necessitates dural puncture at high lumber or thoracic
levels apart from the conventional spinal below L1 .
► Lower the dose of local anaesthetic drug used more likely it to
produce a true segmental block.

13. ► There are three main issues related to spinal at unconventional
levels
► 1) risk of neuronal injury
► 2) respiratory embarrassment due to extensive thoracic nerve
blockade and
► 3) cephalad spread of local anaesthetic drugs causing high or total
block.

14. Advantages of segmental spinal over routine
spinal or GA at times ?
► a) surgeries which were thought to be out of domain of spinal anaesthesia are
possible with segmental spinal , like upper abdominal surgeries, superficial thoracic
and breast surgeries, thoracoscopic procedures like bullectomy, thymectomy, lung
volume reduction and wedge resection.
► b) higher levels of blocks can be achieved with just half the dose which would
have required with spinal given at lumber levels. That means fewer haemodynamic
fluctuations , early recovery, and voiding.
► c) special advantages over GA in patients with pre existing respiratory co
morbidities. It can avoid postop pulmonary complications and patients going on
ventilatory support.
► d) lower incidence of postop nausea and vomiting

15. which drugs can be used for segmental
spinal ? Can hyperbaric drugs be used
► both isobaric and hyperbaric drugs can be used for segmental
spinal and even a combination of both also can be used for some
abdominopelvic surgeries. In general isobaric drugs are preferred for
laparoscopic and thoracic surgeries and hyperbaric can be a
choice in open surgeries specially in male muscular patients where
relaxation can be a issue. Amongst the available drugs -
Chlorprocaine 1%, Levobupivacaine 0.5%, Ropivacaine 0.5 & 0.75 %
, Bupivacaine 0.5 % heavy all can be used as per need.

16. ► On an average one ml of isobaric drug spreads two to three
segments above and below the site of injection. That means 2 to 2.5
ml of drug is sufficient to block segments from T2 to L5/S1 if spinal
given at T10 In general for all lap abdominal surgeries of 60 to 90
mins duration , a dose of 2ml of isobaric levobupivacaine with
fentanyl 25 mcg for Female patients and 2.5 ml levobupivacaine +
25 mcg fentanyl for male patients given at T10/12 level.

17. ► a combination of hyperbaric and isobaric drugs can be used. 0.5 ml
of hyperbaric bupivacaine followed by 2ml of isobaric
levobupivacaine from different syringe , in sitting position spinal at T
10/12 level. This can work for procedures like TLH or other
abdominopelvic surgeries for upto 2 hrs or more depending on
additive used. For prolonged surgeries and in patients with multiple
co-morbidities where we want to use very minimal dose in spinal
(just 1 to 1.5 ml ) , epidural can be placed at same level (CSE kit ) or
one space above . Epidural can be helpful not only during surgery
and postop analgesia but also by EVE (epidural volume extension
technique ) low dose of spinal can be spread to more segments.

18. ► For thoracic and breast surgeries –
► spinal at midthoracic levels (T5/6/7) with 1 to 1.2 ml of isobaric
levobupivacaine ( max 1.5 ml with additive ) with 25 mcg fentanyl
can work for 60 minutes . For longer duration surgeries better to
combine with epidural rather than increasing the intrathecal dose,
to avoid haemodynamic and respiratory complications.

19. FACTORS RESPONSIBLE FOR SUCCESS WITH LOW DOSE AT
THORACIC LEVELS
► The amount of CSF at thoracic levels is diminished compared to lumber
and cervical levels. Thoracic nerve roots are very slight (thinner) compared
to segments above and below. Thus there is less anaesthetic dilution per
segmental unit of distance from the site of injection and roots are easily
blocked due to small size.
► Onset time with isobaric solution in the lumber segments is longer than
with the hyperbaric solution. When the injection is given in the thoracic
segments the difference is not significant with solutions.

20. Accidental perforation of the
dura mater during thoracic
epidural block
An anatomical explanation for the lack
of damage was proposed by Imbelloni
and Gouveia].
In MRI the following measures were
found bet pot dura and spinal cord
5.19 mm in T2,
7.75 mm in T5 and
5.88 mm in T10, or let us say,
suficient distance to permit the careful
advancement of a needle (accidentally
of intenionally) without reaching the
medula and administer anesthetic for a
segmental spinal anesthesia.

21. ► Fact that anaesthetic technique is not usual does not mean that it is
wrong.
► A concept has developed that regional anaesthetic should need
no supplements and that if it does , it should be considered a failed
block. This reasoning needs rethinking.
► Patient safety takes precedence over the unnecessary risks to be
taken for the success of the procedure.
► This technique is reserved for experienced clinicians working in
defined and approved evaluation programmes.

22. ► Low dose segmental spinal is associated with remarkable cardio-
vascular stability.
► Patients with high BMI, cardiac and respiratory disease may be
considered for day care surgery.
► Advantages demonstrated are –
► minimal haemodynamic fluctuations
► - minimal motor block
► - faster sensory recovery
► - early ambulation and voiding

23. ► Segmental Spinal Anesthesia: A Systematic Review Luiz
Eduardo Imbelloni* , Jaime Weslei Sakamoto, Eduardo
Piccinini Viana, Andre Augusto de Araujo, Davi Pöttker,
Marcelo de Araujo Pistarino Department of Anesthesia,
Hospital Clínicas Municipal São Bernardo do Campo, São
Bernardo do Campo, SP, Brazil