Cesarean section

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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
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Comprehensive
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A cesarean section (also known as C-section or cesarean delivery ) 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. Often women who have had a cesarean delivery will have a subsequent or repeat cesarean delivery to prevent the possibility of uterine rupture during labor. 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
  • Seizures or cerebrovascular accident in patients who progress to eclampsia
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 and increased O2 consumption 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 inhalation 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, e.g. Rotem, Platelet Function, Fibrinogen level

Operating room setup

Patient preparation and premedication

  • Full stomach precautions typically employed if the mother has been laboring prior to cesarean section. There is some controversy regarding whether non-laboring parturients (eg, elective C-section) should be considered "full stomachs".
  • Nonparticulate oral antacid (e.g. sodium citrate) immediately prior to general or regional anesthesia.
  • Intravenous promotility agent (eg. 10 mg metoclopramide given over 5-10 minutes). Patients may experience akathisia if given too rapidly.
  • Intravenous antacids (e.g. ranitidine, famotidine). Onset of action 30 minutes.
  • Anxiolysis (benzodiazepines or opiates) not typically used unless patient is extremely anxious due to concern for fetal respiratory depression from placental transfer
  • 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

  • Neuraxial anesthesia is preferred unless there are strict contraindications (eg, patient refusal, inadequate anesthesia with existing epidural in an emergency situation, thrombocytopenia in the setting of pre-eclampsia or HELLP). General anesthesia with volatile anesthetics exposes the mother to the risk of difficult airway secondary to upper airway edema and increased bleeding due to uterine relaxation.
    • Elective C-section
      • Spinal anesthesia employed with 10-12.5 mg of hyperbaric bupivacaine (0.75% in dextrose), 15 mcg of fentanyl, and 100-200 mcg of morphine.
      • If risk factors for prolonged duration of surgery are present such as obesity, prior C-section, or prior abdominal surgery, 5 mcg of epinephrine can be added to the spinal anesthetic dose to prolong duration of blockade.
    • Urgent C-section in laboring parturient
      • Existing labor epidural should be utilized and dosed with 2% lidocaine for rapid achievement of surgical anesthesia to the level of T4.
        • 2 mL of bicarbonate and 5 mcg of epinephrine can be added to the lidocaine to speed the onset of action.
        • 0.5% bupivacaine can also be utilized if there is adequate time for its onset of action (10-15 minutes).
        • 100 mcg of epidural fentanyl can be administered to increase the density of the block.
      • Spinal anesthesia should be attempted if there is sufficient time (stability of fetal heart rate tracing)
    • Emergency C-section
      • 20 mL of 3% chloroprocaine should be administered through an existing epidural catheter to achieve rapid surgical anesthesia (roughly 8 minutes to peak effect)
      • General anesthesia should be employed if surgical anesthesia cannot be obtained with an existing epidural or if there is no epidural in place.
        • RSI with propofol and succinylcholine (etomidate if concern for cardiovascular instability).
        • Smaller ETT size generally used (6.0-6.5) due to concern for maternal airway edema in the setting of labor.
        • Sevoflurane used for maintenance of anesthesia initially and 70% nitrous oxide in 30% oxygen after delivery of the fetus to reduce the amount of sevoflurane (which has a higher tendency to produce tocolysis and increase bleeding). Opiates (eg, hydromorphone) can be administered after delivery of the fetus.
  • 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 of
  • 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)