Cesarean section

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Revision as of 02:43, 20 July 2022 by Adam Harari (talk | contribs) (added to hematologic effects during pregnancy)
Cesarean section
Anesthesia type

Neuraxial or general

Airway

ETT if general

Lines and access

Large bore IV x2

Monitors

Standard Fetal heart rate monitor

Primary anesthetic considerations
Preoperative

Full stomach precautions Aspiration prophylaxis Left lateral tilt

Intraoperative

Have uterotonics available

Postoperative
Article quality
Editor rating
Comprehensive
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A cesarean section (also known as C-section) is a surgical procedure where the baby is delivered through an incision in the uterus. C-sections are typically performed when a vaginal delivery would put the mother or baby at risk. In the USA, about 32% of deliveries are via Cesarean section[1], and worldwide the figure is approximately 21%.[2]

Preoperative management

Patient evaluation

System Considerations
Neurologic
Cardiovascular
  • Pregnant patients typically have decreased systemic vascular resistance, decreased diastolic pressure, decreased MAP, increased HR, and increased CO.
  • Left uterine tilt to minimize aortocaval compression[3]
  • Evaluate for pregnancy induced hypertension (PIH)
Pulmonary
  • Pregnant patients typically have compensated respiratory alkalosis, increased minute ventilation, decreased FRC, and increased oxygen consumption.
  • Decreased FRC results in rapid desaturation if ventilation is compromised.
  • Atelectasis can occur secondary to an elevated diaphragm, thereby causing V/Q mismatch and decreased PaO2.
  • Increased MV and decreased FRC increase uptake of inhalational agents.
  • Mucosal capillary engorgement in upper airway may necessitate smaller endotracheal tube.
Gastrointestinal / Hepatic
  • Increased gastric pressure
  • Decreased esophageal sphincter tone
  • Decreased gastric motility
  • Full stomach precautions
  • Risk for aspiration
  • Liver enzymes may be mildly elevated
    • Check for HELLP
Hematologic
  • Increased RBC mass, plasma volume, and blood volume
  • Leukocytosis
  • Iron deficiency anemia + dilutional anemia of pregnancy
  • Excessive blood loss possible with uterine atony, multiple gestation, previous C-section, placental pregnancy, placental abruption, pregnancy induced hypertension, or prolonged labor.
  • Pregnancy is associated with a hypercoagulable state as a way to blunt the blood loss anticipated during delivery, however, this physiologic adaptation predisposes them to DVT/PE formation.
Renal
  • Increased renal blood flow, GFR, and creatinine clearance
  • Decreased serum creatinine and BUN
  • Dependent edema secondary to increased water and sodium retention
Other

Labs and studies

  • T&S
  • T&C only if significant blood loss anticipated
  • Coagulation panel
  • Chemistry panel
  • Complete Blood Count (CBC)
  • Other tests as indicated by H&P

Operating room setup

Patient preparation and premedication

  • Full stomach precautions
  • Nonparticulate oral antacid (e.g. sodium citrate) immediately prior to general or regional anesthesia
  • Intravenous promotility agent (eg. metoclopramide)
  • Intravenous antacids (e.g. ranitidine, famotidine)
  • Anxiolysis not typically used unless patient is extremely anxious
  • Elevate the right hip to provide left uterine displacement
  • Adjunctive azithromycin 500mg IV to standard beta-lactam antibiotics shown to reduce the incidence in endometriosis and wound infection occurring in the first 6 weeks after Cesarean Section[4].

Regional and neuraxial techniques

  • Epidural, spinal, and combined spinal-epidural (CSE) techniques are all commonly employed
    • Check coagulation and platelets prior to neuraxial anesthesia
  • Post-operative transversus abdominal block (TAP block) or quadratus lumborum block.
  • Post-operative elastomeric pain pumps with local anesthetic may be useful for incisional pain

Intraoperative management

Monitoring and access

  • Standard monitors

Induction and airway management

  • Avoid nasal airways due to potential for mucosal capillary engorgement in upper airway

Positioning

  • Left lateral tilt (15o) to avoid aortocaval compression and supine hypotension.

Maintenance and surgical considerations

  • Anticipate EBL of 700-1000 mL
    • Be prepared for excessive blood loss if underlying risk factors
  • Immediately post-partum, ~600-800 mL of blood will enter the central circulation (placental autotransfusion), which will increase cardiac output
  • Tranexamic acid 1g administered over 30-60 seconds during the first 3 minutes after birth, and after the uterotonic agent has been administered (e.g. oxytocin) is shown to reduce the incidence of post-operative blood loss > 1000 mL by POD #2 or RBC transfusion[5].
  • Start oxytocin 30U in 500mL fluid over 3 hours after clamping of umbilical cord
  • Monitor for hemodynamic variance (e.g. hypotension) after starting oxytocin
  • Additional uterotonics may be requested by surgeon if uterine tone is not adequate (e.g. methylergonovine, carboprost, misoprostol)

Emergence

Postoperative management

Disposition

  • L&D PACU
  • Operating room PACU

Pain management

  • Epidural morphine 1-3mg for long acting post-partum pain relief[6][7]
  • IT morphine 50-150mcg for long acting post-partum pain relief if spinal performed[8]
  • IV acetaminophen
  • Ibuprofen PO post-op
  • ± Ketorolac (dependent upon surgeon preference and total blood loss)
  • ± Wound infiltration
  • ± Transversus abdominal block (TAP block) or quadratus lumborum block (for patients undergoing general anesthesia or neuroaxial without intrathecal opioid administration)
  • ± Continuous local anesthetic pain pump

Potential complications

  • Ureteral injury
  • Post-partum hemorrhage

Procedure variants

Neuraxial General
Unique considerations
  • Decreased BP common with spinal anesthesia
  • Given fluid pre-load or co-load
  • Be prepared to provide bolus as vasopressors as needed
  • GA normally used when neuraxial contraindicated or when there is not enough time to perform a block due to obstetric emergency
  • Rapid sequence induction (RSI)
Position Left lateral tilt Left lateral tilt
Surgical time 45-90min 30-45min (given emergency delivery indications)
EBL 500-1000mL 500-1000mL
Postoperative disposition L&D PACU L&D or OR PACU
Pain management 4 6
Potential complications Post-dural-puncture headache
  • Aspiration
  • Difficult Airway

References

  1. "FastStats". www.cdc.gov. 2021-03-24. Retrieved 2021-05-27.
  2. Boerma, Ties; Ronsmans, Carine; Melesse, Dessalegn Y.; Barros, Aluisio J. D.; Barros, Fernando C.; Juan, Liang; Moller, Ann-Beth; Say, Lale; Hosseinpoor, Ahmad Reza; Yi, Mu; Neto, Dácio de Lyra Rabello (2018-10-13). "Global epidemiology of use of and disparities in caesarean sections". The Lancet. 392 (10155): 1341–1348. doi:10.1016/S0140-6736(18)31928-7. ISSN 0140-6736. PMID 30322584.
  3. Buley, R. J.; Downing, 4 W.; Brock-Utne, J. G.; Cuerden, C. (1977-10). "Right versus left lateral tilt for Caesarean section". British Journal of Anaesthesia. 49 (10): 1009–1015. doi:10.1093/bja/49.10.1009. ISSN 0007-0912. PMID 921864. Check date values in: |date= (help)
  4. Tita, Alan T.N.; Szychowski, Jeff M.; Boggess, Kim; Saade, George; Longo, Sherri; Clark, Erin; Esplin, Sean; Cleary, Kirsten; Wapner, Ron; Letson, Kellett; Owens, Michelle (2016-09-29). "Adjunctive Azithromycin Prophylaxis for Cesarean Delivery". New England Journal of Medicine. 375 (13): 1231–1241. doi:10.1056/NEJMoa1602044. ISSN 0028-4793. PMC 5131636. PMID 27682034.CS1 maint: PMC format (link)
  5. Sentilhes, Loïc; Sénat, Marie V.; Le Lous, Maëla; Winer, Norbert; Rozenberg, Patrick; Kayem, Gilles; Verspyck, Eric; Fuchs, Florent; Azria, Elie; Gallot, Denis; Korb, Diane (2021-04-29). "Tranexamic Acid for the Prevention of Blood Loss after Cesarean Delivery". New England Journal of Medicine. 384 (17): 1623–1634. doi:10.1056/NEJMoa2028788. ISSN 0028-4793.
  6. Fuller, John G.; McMorland, Graham H.; Douglas, M. Joanne; Palmer, Lynne (1990-09). "Epidural morphine for analgesia after Caesarean section: a report of 4880 patients". Canadian Journal of Anaesthesia. 37 (6): 636–640. doi:10.1007/BF03006481. ISSN 0832-610X. Check date values in: |date= (help)
  7. Bollag, Laurent; Lim, Grace; Sultan, Pervez; Habib, Ashraf S.; Landau, Ruth; Zakowski, Mark; Tiouririne, Mohamed; Bhambhani, Sumita; Carvalho, Brendan (2021-05). "Society for Obstetric Anesthesia and Perinatology: Consensus Statement and Recommendations for Enhanced Recovery After Cesarean". Anesthesia & Analgesia. 132 (5): 1362–1377. doi:10.1213/ANE.0000000000005257. ISSN 0003-2999. Check date values in: |date= (help)
  8. Bollag, Laurent; Lim, Grace; Sultan, Pervez; Habib, Ashraf S.; Landau, Ruth; Zakowski, Mark; Tiouririne, Mohamed; Bhambhani, Sumita; Carvalho, Brendan (2021-05). "Society for Obstetric Anesthesia and Perinatology: Consensus Statement and Recommendations for Enhanced Recovery After Cesarean". Anesthesia & Analgesia. 132 (5): 1362–1377. doi:10.1213/ANE.0000000000005257. ISSN 0003-2999. Check date values in: |date= (help)