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20 Regional Anesthesia inBariatric Surgery
207
Site of action
of TAP block
Lateral
cutaneous
branch
Intercostal
nerve
Pleura and
endothoracic fascia
Innermost intercostal m.
Internal intercostal m.
Posterior
cutaneous
branches
Anterior cutaneous branch
Sympathetic ganglion
Ventral ramus
External
intercostel m.
Rami communicantes
Dorsal ramus
TP
ESM
RMM
TM
Fig. 20.4 ESP block anatomy. Anatomy of the ESP block. Local anesthetic (in blue) injected
anterior (deep) to the erector spinae muscle (ESM) spreads in a cranial direction along this tissue
plane. Also enters the thoracic paravertebral space to anesthetize not only the ventral ramus and
dorsal ramus of the spinal nerve, but also the white and gray rami communicants that carry the
preganglionic and postganglionic sympathetic bers to and from the sympathetic ganglia. The ESP
block thus has the potential to provide both somatic and visceral analgesia to the trunk. Source:
Chin, K.J., Malhas, L., & Perlas, A. (2017). The Erector Spinae Plane Block Provides Visceral
Abdominal Analgesia in Bariatric Surgery: A Report of 3 Cases. Regional Anesthesia and Pain
Medicine, 42(3), 372–376. https://doi.org/10.1097/AAP.0000000000000581
ab
Fig. 20.5 ESP block. Targets a plane that is far removed from the pleura and neuraxial structures.
Target transverse process is determined by surface landmarks or using the probe to count up from
the 12th rib or down from 1srt rib (a, b)
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Fig. 20.6 ESP block. Erector spinae approach. Source: Chin, K.J., Malhas, L., & Perlas, A. (2017).
The Erector Spinae Plane Block Provides Visceral Abdominal Analgesia in Bariatric Surgery: A
Report of 3 Cases. Regional Anesthesia and Pain Medicine, 42(3), 372–376. https://doi.
org/10.1097/AAP.0000000000000581
A. Teixeira et al.
Fig. 20.7 ESP block. Ultrasound image of the erector spinae block performed at L4 transverse
process. Source: Harbell, M.W., Seamans, D.P., Koyyalamudi, V., Kraus, M.B., Craner, R.C., &
Langley, N.R. (2020). Evaluating the extent of lumbar erector spinae plane block: An anatomical
study. Regional Anesthesia & Pain Medicine, 45(8), 640–644. https://doi.org/10.1136/
rapm- 2020- 101523 [11]
In the case report study realized by (Chin etal., 2017), three patients underwent
ESP block with 20mL of 0.5% ropivacaine. The results indicated that ESP block
has provided signicant relief of upper abdominal pain [10].
These three cases illustrated that the ESP block may hold potential as a rela-
tively simple regional anesthesia technique, providing both visceral and
somatic analgesia in postoperative pain following laparoscopic bariatric
20 Regional Anesthesia inBariatric Surgery
209
surgery, however, the authors suggested further clinical investigation, including
prospective randomized controlled trials, to clearly establish the potential efcacy
of ESP block as an analgesic modality in laparoscopic bariatric surgery [10, 16].
In a clinical trial realized by (Mostafa etal., 2021), which was the rst prospective randomized trial to investigate the impacts of ESPB on perioperative analgesia,
and pulmonary functions in patients suffering from morbid obesity for bariatric
surgery using laparoscopy. Showed that bilateral ultrasound guided ESPB effec-
tively provided lower postoperative pain score in the rst 8 postoperative hours
with decreased perioperative analgesic consumptions. Measured as signicant
reduction in postoperative VAS scores for the rst 8h, intraoperative fentanyl
consumption as well as the rst 24h postoperative cumulative morphine consumption. Nevertheless, no signicant differences in postoperative pulmonary
functions were detected between both groups [14].
20.4 Conclusion
Enhanced Recovery After Surgery (ERAS) protocols suggest the implementation of
regional techniques such as USG-TAP and USG-ESP block as part of multimodal
analgesia for postoperative pain management, in patients undergoing laparoscopic
bariatric surgery. These procedures can have utility when neuraxial techniques or
opioids are contraindicated [4, 16]. Multimodal systemic medication and local anesthetic inltration techniques should be combined, since there is a strong scientic
evidence that regional block procedures as TAP or, more recently ESP blockade
provides several benets in the pain management setting, with less use of opioids
compared to traditional techniques and may decrease the level of stress,
decrease incidence of thromboembolic complications, and length of recovery
after surgery, as well as provides higher rates of patient satisfaction [4, 12]. It has
also shown that regional anesthesia preserves immune function better than general
anesthesia and opioids [6, 7].
References
1. Regional Anesthesia for Bariatric Surgery: Bariatric Times. n.d. https://bariatrictimes.com/
regional- anesthesia- for- bariatric- surgery/. Accessed 30 Mar 2021.
2. Thorell A, MacCormick AD, Awad S, Reynolds N, Roulin D, Demartines N, etal. Guidelines
for perioperative care in bariatric surgery: enhanced recovery after SURGERY (ERAS)
Society recommendations. World J Surg. 2016;40(9):2065–83. https://doi.org/10.1007/
s00268- 016- 3492- 3.
3. Singh PM, Panwar R, Borle A, Goudra B, Trikha A, van Wagensveld BA, Sinha A.Efciency
and safety effects of applying ERAS protocols to bariatric surgery: a systematic review with
meta-analysis and trial sequential analysis of evidence. Obes Surg. 2017;27(2):489–501.
https://doi.org/10.1007/s11695- 016- 2442- 3.
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A. Teixeira et al.
4. Wassef M, Lee D, Levine J, Ross R, Guend H, Vandepitte C, Hadzic A, Teixeira J.Feasibility
and analgesic efcacy of the transversus abdominis plane block after single-port laparoscopy in patients having bariatric surgery. J Pain Res. 2013;2013:837. https://doi.org/10.2147/
JPR.S50561.
5. Weinstein EJ.Local and regional anaesthesia at the time of surgery to prevent longer-term
persistent pain after surgery. 2018. https://www.cochrane.org/CD007105/ANAESTH_local-
and- regional- anaesthesia- time- surgery- prevent- longer- term- persistent- pain- after- surgery.
Accessed 29 Mar 2021.
6. Hung W-C, Chen W-H, Shih Y-H, Hung K-C.Epidural anesthesia for laparoscopic bariatric surgery: a case report. Springerplus. 2015;4(1):363. https://doi.org/10.1186/s40064- 015- 1153- x.
7. Tran dQ, Bravo D, Leurcharusmee P, Neal, JM.Transversus abdominis plane block: a narrative
review. 2019. https://pubmed.ncbi.nlm.nih.gov/31283738/. Accessed 29 Mar 2021.
8. Tran DQ, Bravo D, Leurcharusmee P, Neal JM. Transversus abdominis plane block.
Anesthesiology. 2019;131(5):1166–90. https://doi.org/10.1097/ALN.0000000000002842.
9. Moon RC, Lastrapes L, Wier J, Nakajima M, Gaskins W, Teixeira AF, Jawad MA.Preoperative
transversus abdominis plane (TAP) block with liposomal bupivacaine for bariatric patients to
reduce the use of opioid analgesics. Obes Surg. 2019;29(4):1099–104. https://doi.org/10.1007/
s11695- 018- 03668- 5.
10. Hytham HK, Amjed AY, Alan SA, Sameh EH, Mohamed I, Ruiz-Tovar J.Transversus abdominis plane block using a short-acting local anesthetic reduces pain and opioid consumption
after laparoscopic bariatric surgery: a meta-analysis. 2020. https://www.soard.org/article/
S1550- 7289(20)30207- 0/fulltext. Accessed 30 Mar 2021.
11. Harbell MW, Seamans DP, Koyyalamudi V, Kraus MB, Craner RC, Langley NR.Evaluating
the extent of lumbar erector spinae plane block: an anatomical study. Reg Anesth Pain Med.
2020;45(8):640–4. https://doi.org/10.1136/rapm- 2020- 101523.
12. McCarthy RJ, Ivankovich KG, Ramirez EA, Adams AM, Ramesh AK, Omotosho PA,
Buvanendran A. Association of the addition of a transversus abdominis plane block to an
enhanced recovery program with opioid consumption, postoperative antiemetic use, and discharge time in patients undergoing laparoscopic bariatric surgery: a retrospective study. Reg
Anesth Pain Med. 2020;45(3):180–6. https://doi.org/10.1136/rapm- 2019- 101009.
13. Földi M, Soós A, Hegyi P, Kiss S, Szakács Z, Solymár M, Pétervári E, Balaskó M, Kusza K,
Molnár Z.Transversus abdominis plane block appears to be effective and safe as a part of multimodal analgesia in bariatric surgery: a meta-analysis and systematic review of randomized
controlled trials. Obes Surg. 2021;31(2):531–43. https://doi.org/10.1007/s11695- 020- 04973- 8.
14. Mostafa SF, Abdelghany MS, Abu Elyazed MM.Ultrasound-guided erector spinae plane block
in patients undergoing laparoscopic bariatric surgery: a prospective randomized controlled
trial. Pain Pract. 2021;21(4):445–53. https://doi.org/10.1111/papr.12975.
15. Torensma B, Martini CH, Boon M, Olofsen E, etal. Deep neuromuscular BLOCK improves
surgical conditions during bariatric surgery and Reduces Postoperative PAIN: a randomized
double blind controlled trial. PLoS One. 2016;11(12):e0167907. https://doi.org/10.1371/jour-
nal.pone.0167907.
16. Brogi E, Kazan R, Cyr S, Giunta F, Hemmerling TM.Transversus abdominal plane block for
postoperative analgesia: a systematic review and meta-analysis of randomized-controlled trials. Can J Anesth. 2016;63(10):1184–96. https://doi.org/10.1007/s12630- 016- 0679- x.
17. Urits I, Ostling P, Novitch M, Burns J, Charipova K, Gress K, etal. Truncal regional nerve
blocks in clinical anesthesia practice. 2019. https://www.sciencedirect.com/science/article/
abs/pii/S1521689619300576?via%3Dihub. Accessed 29 Mar 2021.
18. Chin KJ, Malhas L, Perlas A.The erector spinae plane block provides visceral abdominal
analgesia in bariatric surgery: a report of 3 cases. Reg Anesth Pain Med. 2017;42(3):372–6.
https://doi.org/10.1097/AAP.0000000000000581.
Chapter 21
Multimodal Analgesia inBariatric Surgery
AndreTeixeira, AdamEl Kommos, andLauraV.MedinaAndara
21.1 Introduction
Pain control after bariatric surgery represents a major challenge for the perioperative team. Comorbidities in the bariatric population such as obstructive sleep apnea,
hyper-coagulopathies, and metabolic syndromes prevent this patient population
from more traditional postoperative pain management strategies. The goals of postoperative pain management in the bariatric population are to provide adequate comfort while fostering early mobilization with minimal respiratory depression. One
such strategy that has been recently popularized is multimodal analgesia.
Multimodal analgesia is a pharmacologic method of pain management which
combines various groups of medications for pain relief. Its purpose is to target more
than one pain mechanism, therefore diminishing adverse side effects of any drug
class: especially opioid-induced respiratory complications. Typical drug classes in
multimodal analgesia include acetaminophen, nonsteroidal anti-inammatories,
local anesthetics, alpha-2 inhibitors, steroids, calcium channel blockers, and NDMA
antagonist. In addition to drug classes, other strategies implored with the multimodal analgesia method include peripheral nerve blocks, local wound inltration,
and neural-axial techniques. However, it is important to also recognize that even
with the implementation of multimodal analgesia, there is a role for opiates during
the patient’s hospital course: primarily as a rescue analgesic in reduced dosing.
A. Teixeira (*)
Orlando Health Bariatric Surgery and Weight-Loss Institute, Orlando, FL, USA
A. El Kommos · L. V. MedinaAndara
Department of Anesthesia, Orlando Health Anesthesia, Orlando, FL, USA
© The Author(s), under exclusive license to Springer Nature
Switzerland AG 2023
A. Teixeira et al. (eds.), Duodenal Switch and Its Derivatives in Bariatric and
Metabolic Surgery, https://doi.org/10.1007/978-3-031-25828-2_21
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21.2 Opiates
Opioids have been the mainstay for postoperative pain relief in patients undergoing
laparoscopic bariatric surgery for many decades and are often critical for perioperative pain management. Opioids mimic the actions of endogenous opioid peptides by
interacting with mu-, delta-, or kappa-opioid receptors. The adverse effects of prescription opioids are well documented. Opioids are associated with immunosuppression, opioid-induced endocrinopathy (sexual dysfunction, depression, and
decreased energy), hyperalgesia, nausea, vomiting, constipation, physical dependence, delayed gastric emptying, tolerance, and respiratory depression. Hyperalgesia
has been demonstrated with exposure to both short- and long-term opioids [1].
Respiratory depression secondary to opiates in the bariatric surgery population is
one of the primary reasons why multimodal analgesia is implemented.
21.3 Acetaminophen
Acetaminophen also called paracetamol is one of the most widely used analgesic
drugs due to its good tolerance and high safety prole. The exact mechanism of
action (MOA) of acetaminophen is not known. Acetaminophen can be administered
in various ways; an intravenous (IV) formulation was approved by the US Food and
Drug Administration (FDA) in 2010 for mild to severe pain as an adjunct to opioids
[2]. Bariatric surgeries can alter the absorption of medications leading to decreased
bioavailability, absorption, and effectiveness; thus, IV acetaminophen is the preferred route for these types of surgeries [3]. Acetaminophen has been proven to be
benecial in decreasing the length of hospitalization, opioid consumption, and pain;
however, its results are not the same in all the surgeries [2].
Recent trials have been exploring the role of intravenous (IV) acetaminophen in
multimodal analgesic therapy in bariatric surgery. Patients who received IV acetaminophen 1 g every 6 h during the 24-h postoperative period consumed fewer
intravenous morphine equivalents and had similar pain scores as patients who were
treated with opioids alone. These patients also had earlier return of bowel function
[4, 5]. Overall, the studies suggest that the use of IV acetaminophen after bariatric
surgery is effective in reducing postoperative pain scores and opioid doses in these
patients [5]. The use of IV acetaminophen is a rational rst-line opioid adjuvant for
postoperative pain management in bariatric patients and should be concerned as a
scheduled medication [6].
21 Multimodal Analgesia inBariatric Surgery
213
21.4 Nonsteroidal Anti-Inammatory Drugs (NSAIDs)
NSAIDs include ibuprofen, naproxen, indomethacin, ketorolac, and diclofenac, a
class of medication commonly used as an analgesic to reduce myofascial pain, postoperative pain, and chronic pain conditions. NSAIDs are potent analgesics (600mg
of ibuprofen is as efcacious as 15mg of oxycodone hydrochloride) and act through
inhibition of cyclooxygenase and prostaglandin synthesis [5], thus blocking the sensitization of pain receptors by blocking the inammatory cascade that occurs during
surgery.
A randomized controlled trial highlighted by the Safety Program for Improving
Surgical Care and Recovery (ISCR) showed that the use of IV ketorolac versus
placebo in patients undergoing laparoscopic gastric bypass surgery was associated
with lower pain scores, improved ability to cooperate with respiratory physical therapy, and improved postoperative patient satisfaction [7]. However, a study carried
out between January 2016 and January 2017 showed that an intravenous administration of 800mg ibuprofen did not signicantly reduce opioid consumption; however,
it reduced the severity of pain compared with 1g of IV acetaminophen in patients
under bariatric surgery [7].
The use of NSAIDs is controversial. Like opioids, there are numerous side
effects of NSAIDs specic to the bariatric population including gastric irritation,
gastric bleeding, platelet dysfunction, increased risk of cardiovascular disease, and
worsening renal function [8]. Therefore, caution is advised in selecting the appropriate NSAID for a patient after consultation with the perioperative healthcare providers [5].
21.5 N-Methyl-D-Aspartate Antagonists
The N-methyl-D-aspartate (NMDA) class of glutamate receptor is involved with
nociceptive processing and development of chronic pain. Clinically available
NMDA antagonists include ketamine hydrochloride, magnesium sulfate, dextromethorphan hydrobromide, and methadone.
Ketamine is a nonbarbiturate that abolishes peripheral afferent noxious stimulation and may also prevent central sensitization of nociceptors. There are no studies
specically examining the use of intraoperative ketamine alone in patients undergoing bariatric surgery. The administration of a low dose of ketamine and clonidine at
induction of anesthesia is associated with earlier extubation and less pain in open
bariatric surgical patients [7]. The side effects of ketamine include increased sympathetic activity, elevated intracranial pressure, increased salivation, nystagmus,
and hallucinations. Therefore, caution is advised when using ketamine in patients
with coronary artery disease, intracranial pathology, and psychiatric comorbidities [2].
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There were no studies specically for magnesium sulfate in bariatric surgery, but
other sources have indicated that perioperative magnesium infusion is associated
with a decrease in postoperative pain and opioid consumption without clinical toxic
effects caused by toxic serum levels of magnesium [5]. As for dextromethorphan, it
is not commonly reported as an analgesic after bariatric surgery. If the clinician
decides to use dextromethorphan for the bariatric surgical patients, it should be
noted that the optimal dosing of dextromethorphan is uncertain, although typical
doses used range from 30 to 60mg orally given preoperatively and postoperatively
on a twice a day or TID dosing regimen afterward [7].
21.6 Alpha-2 Agonists
The two common alpha-2 agonists used in clinical practice today are clonidine and
dexmedetomidine. They bind to the presynaptic alpha-2 adrenoceptors which inhibit
the release of norepinephrine, therefore terminating the propagation of pain signals.
Dexmedetomidine has a much higher afnity (approximately 8:1) than clonidine at
the alpha-2 receptor site. Both agents may signicantly reduce opioid consumption,
postoperative nausea/vomiting, anxiety, postoperative shivering, and stress
responses intraoperatively [3]. The use of dexmedetomidine has been studied in two
recent papers due to its safety prole regarding respiratory depression and better
hemodynamic stability [2]. In the setting of bariatric surgery, six studies were highlighted by the taskforce (ISCR) suggesting that a perioperative IV infusion of dexmedetomidine may be associated with a decrease in pain scores and opioid
requirements during this period. Patients also had better pain control and a lower
incidence of postoperative nausea and vomiting (PONV) without any reported
major adverse events [7].
21.7 Calcium Channel Blocker
The release of excitatory neurotransmitters including glutamate and pain-inducing
peptides such as substance P from presynaptic sites is stimulated by the opening of
activation of voltage-gated calcium channels and calcium inux; therefore, blocking calcium channels can play a signicant role in modulating both nociceptive and
antinociceptive processes. Gabapentin, pregabalin, zonisamide, ziconotide, and
levetiracetam are examples of drugs that block calcium channels as a part of their
MOAs and have been used in pain management.
Pregabalin and gabapentin were originally used as anticonvulsant, but recent
studies have shown that they can also be used for pain management. Meta-analyses
indicate that a single dose of gabapentin or pregabalin administered preoperatively
is associated with a decrease in postoperative pain and opioid consumption at 24h
but an increase in postoperative sedation, dizziness, and visual disturbances [9].
21 Multimodal Analgesia inBariatric Surgery
There are two small studies examining the preoperative administration of gabapentinoids before bariatric surgery. Both suggest that the administration of preoperative gabapentinoids may result in lower pain levels and less postoperative nausea
and vomiting (PONV) although there may not be a decrease in opioid consumption [9].
However, a study conducted to evaluate the effect of a single dose of preoperative
pregabalin (75mg) vs placebo in patients undergoing bariatric surgery showed that
a single preoperative dose of pregabalin did not improve pain relief, quality of postoperative recovery, or reduction in opioid consumption [5].
215
21.8 Lidocaine Patches
The MOA of lidocaine patch is believed to provide analgesia by reducing aberrant
ring of sodium channels on damaged pain bers directly under the patch. There is
no evidence that lidocaine patches exert any effect in postoperative bariatric surgery
[7]; although, in other sources, lidocaine patches (intradermal) are generally well
tolerated and compared with other opioids and nonopioid analgesics, it has a very
favorable (low risk) adverse effect prole [5] and should be considered for some
patients.
21.9 Tramadol
Tramadol produces analgesia via dual opioid (very weak mu-opioid receptor activation) and nonopioid (inhibits serotonin and norepinephrine reuptake) MOAs [5].
Tramadol produces analgesia with a relatively lower risk of addiction, less constipation, minimal cardiovascular adverse effects, and minimal respiratory depression.
However, the analgesic efcacy of tramadol for bariatric surgical patients is uncertain. Tramadol has less μ-receptor (opioid) activity than morphine and may be a
useful analgesic adjunct because it demonstrates a weak moderate analgesic effect
that is signicantly improved when combined with acetaminophen [5].
21.10 Local Anesthetic Wound Inltration andInfusions
Wound inltration can be performed either as a single injection of local anesthetic
(typically at the conclusion of surgery) or as a continuous infusion of local anesthetic through a catheter at the incision site placed by the surgeon prior to skin closure; the last one has been associated with a decrease in morphine consumption, a
need for opioid rescue, and signicantly lower pain scores within the rst hour.
Studies available on the eld of bariatric surgery investigating the continuous
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infusion of local anesthetic suggest that this technique may be associated with lower
opioid use with no difference in pain score [5]. However, there is not a denitive
conclusion due to the limited data on this eld.
21.11 Conclusion
Over the years, there has been a greater interest about better postoperative pain
management and safety on patients undergoing bariatric surgery. Recently, the
Agency for Healthcare Research and Quality (AHRQ), together with other institutions [7], reviewed evidence-based pathways of care to improve outcomes and
enhance perioperative care and patient safety including patients undergoing bariatric surgery.
This taskforce and other investigations highlighted the importance of multimodal
analgesia in the bariatric population to improve patient outcomes and minimize
adverse outcomes. Multimodal analgesia for bariatric surgery should be implemented by the perioperative team by considering the risks and benets of each drug
class and analgesic strategy, alone and in conjunction with one another.
References
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surgical procedures in the United States, 2004-2012. JAMA. 2016;315(15):1654–7. https://doi.
org/10.1001/jama.2016.0130.
2. Barajas Gamboa MD, Gonzalez Nuñez MD.Pain management in weight loss surgery: aim-
ing for multimodal approach. Adv Obes Weight Manag Control. 2016;5(2):232–7. https://doi.
org/10.15406/aowmc.2016.05.00125.
3. Graff V, Grosh T. Multimodal analgesia and alternatives to opioids for postopera-
tive analgesia. 2019. Retrieved March 30, 2021, from https://www.apsf.org/article/
multimodal- analgesia- and- alternatives- to- opioids- for- postoperative- analgesia/
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1):14S–21S. https://doi.org/10.1002/phar.1517.
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LF, Mello C, Alves RL, Módolo N.Pregabalin to improve postoperative recovery in bariat-
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6. Grant MC, Gibbons MM, Ko CY, Wick EC, Cannesson M, Scott MJ, McEvoy MD, King
AB, Wu CL.Evidence review conducted for the agency for healthcare research and quality
safety program for improving surgical care and recovery: focus on anesthesiology for bariatric
surgery. Anesth Analg. 2019;129(1):51–60. https://doi.org/10.1213/ANE.0000000000003696.
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profen and acetaminophen for postoperative multimodal pain management in bariatric sur-
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jclinane.2018.06.030.
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