Difficult Extractions

There are a multitude of reasons that a caesarean section extraction could be difficult, including a lower segment that is difficult to access, complex fetal positioning, abnormal placentation, or injuries to other organs in the abdomen. Maternal body habitus, as well as multi-fetal pregnancies present additional management considerations and technical challenges for the provider.  

Complicated Fetal Extractions

Deeply impacted fetal head

When performing a caesarean section after prolonged labour, the fetal head is likely impacted deep in the maternal pelvis.

2 methods for overcoming this challenge are prevalent in the literature:

• “Push Method”
  • Patient is placed in lithotomy position, while an assistant pushes deeply impacted fetal head out of pelvis through the vagina
• “Reverse Breech Extraction / Pull Method”
  • Surgeon extracts fetus by the breech

Clinical pearls: (when anticipating a difficult extraction) 
1. Preoperative: 
– Disimpact the fetal head after the spinal or epidural top up prior to scrubbing and prepping 
– Place the patient in lithotomy to allow a nurse or assistant to disimpact during the c-section 

2. Intraopterative: 
– Ask anesthesia to give nitroglycerine  
– Consider putting the patient in Trendenlenburg  
– Do not disimpact when a contraction is happening, wait until it is over 
– Switch hands to non-dominant to disimpact, andthen back to dominant to bring fetal head to incision 
– Ask a nurse or assistant to help disimpact from below 
– Internal podalic version to breech presentation and then doing a breech extraction (intra-uterine version may be most easily achieved by finding the fetal head, as it is easily identifiable, and pushing it to the fundus) 
– Consider a T-incision to allow more room  

• Literature available indicates the Reverse Breech Extraction Method is superior with respect to maternal complications, including lower risk of uterine incision extension and post-partum endometritis^3,4 
• Operation duration is also significantly lower for the Reverse Breech Extraction method, which may correspond with ease of delivery and lower risk of trauma and bleeding⁴ 
• Conversely, a meta-analysis by Jeve et al. found that the “Push Method” bore a significantly higher risk of incision extension, infection, bleeding, and prolonged operative time⁵ 

• The literature suggests there is no significant difference between these techniques when it comes to the risk of fetal complications, bladder and urethra injury risk, and uterine artery / broad ligament injury³ 
• There is also insufficient evidence to support the Patwardhan and “Fetal Pillow” methods over the aforementioned techniques⁵ 

Transverse Lie

• Affects approximately <0.5% of pregnancies and is an indication for Caesarean section3
• A traditional low-isthmic transverse uterine incision is the best choice for cases of transverse lie, and less than 8% of patients will require conversion to an inverted T-incision due to problematic extraction.6,7
• Following hysterotomy, the fetus can then be manipulated through intrauterine-version; the transverse lie is then converted to a longitudinal presentation. Thereafter, the fetal extraction is performed in breech or in cephalic presentation.8
• An important technical consideration is to avoid extension of the hysterotomy, which is associated with increase blood loss and operative duration

Clinical pearl:
A pre-cesarean ultrasound can be helpful when transverse lie is known. Usually it is transverse back down lie that will be most challenging, therefore if known ahead of time, can modify incision or obtain more experienced assistance.

Difficult Access to Lower Uterine Segment

Fibroids

• The most common benign gynecological tumor, and frequently increases in size through the second and third trimester.³ 
• Typically, caesarean myomectomies are discouraged due to bleeding risk.  

• There is evidence indicating that removal increases Hgb drop in the post-operative period, but the risk of transfusion is not significantly increased.³  As such, it may be acceptable to remove fibroids if access to the lower segment is improved or if it facilitates extraction of the fetus.  

Obesity

• Obesity is associated with an increased likelihood of Caesarean section and wound complications³ 
• Transverse skin incisions are associated with lower risk of wound complications, and also improve access to the uterine lower segments, facilitating extraction of the fetus.  

Clinical pearl:
A pre-cesarean ultrasound to determine the location of the lower segment will help guide the incision especially if there is an over-hanging pannus. Sometimes the incision has to be supraumbilical.

Pre-operative taping of the pannus (like suspenders) either to patient’s shoulder to the head of the bed or use of retractor (e.g., Traxi panniculus retractor) can help with access and retraction  

Previous Abdominal Surgery

• Adhesions are common following previous Caesarean sections and abdominal surgery. 
• Adhesions make it difficult to identify critical structures such as the urinary bladder and ureters, increase bleeding risks, and can impede timely extraction of the fetus 
• 2 mechanisms have been proposed to reduce the incidence of adhesions in patients undergoing caesarean section (primary prevention), including peritoneal closure and adhesion barriers. There is however limited evidence in the literature supporting the efficacy of these options.³ 

Multiple Gestation Pregnancy

• There are additional risks when multi-fetal gestation is considered   
• This includes preterm labor, uterine contractile dysfunction, abnormal presentation, cord prolapse, premature placental separation, and post-partum hemorrhage⁹ 
• A number of presentations/positions are possible in twin pregnancies, and these have an implication on delivery management:  

Cephalic – Cephalic presentation  

• Planned caesarean section does not improve neonatal outcomes when both twins are cephalic; if the first twin is cephalic, delivery can be accomplished vaginally either spontaneously or with instrument assistance⁹ 

Cephalic – Non Cephalic Presentation  

• Optimal delivery method is controversial  
• If second non-cephalic twin is > 1500g EFW, vaginal delivery is reasonable; if < 1500g, the recommendations from evidence are less clear but vaginal delivery is still considered safe.⁹ 

Breech Presentation 

• If the first fetus presents as breech, complications may arise if the fetus is unusually large or small, or if the umbilical cord prolapses.  

• If these problems are anticipated or identified, caesarean delivery is indicated⁹ 
• Even without these issues identified, provider or patient preference may be for caesarean delivery.  Some centres may offer vaginal delivery when the presenting twin is breech as there is evidence suggesting no difference in infant mortality⁹ 

Surgical Planning Considerations⁹: 

• The uterine incision should be large enough to facilitate atraumatic delivery of the fetuses and minimize traumatic traction on uterine/adnexal tissues 
• In certain patients, a vertical incision in the uterine lower segment may be helpful 

• When the second twin is breech and the head is obstructed, Piper Forceps delivery may be helpful  

Triplet & Higher Order Gestations 

• Given the possible risks to both mother and fetus, as well as limited evidence, many providers prefer to deliver higher order gestations via caesarean section.  There are certain circumstance and indications where providers may be willing to provide vaginal delivery, but this is provider- and centre-specific⁹ 

Abnormal Placentation

Placenta previa  

• Caesarean section is considered the safest method of delivery with placentation less than 2cm from the internal uterine orifice¹⁰ (as is the case with placenta previa) 
• An incision can be made in the lower uterine segment, taking care to avoid cutting through placenta. If the placenta is cut into, the umbilical cord should be promptly clamped¹⁰ 
• In cases of prematurity, transverse placentation, or when future fertility is not desired, high vertical incision is justified in order to avoid accidental placental injury¹⁰ 

Placenta Accreta 

• Occurs when chorionic villi invade uterine myometrium.  
• General approach accepted in the literature is to perform a caesarean section, and leave the placenta in situ after delivery^11,12 
• When the placenta does not spontaneously detach from the uterus and/or when a massive hemorrhage is taking place, an emergency hysterectomy may be indicated.¹³ 
• Surgical Planning Considerations:  
  • The location of the skin and uterine incision must be chosen carefully to allow adequate uterine access for delivery and a possible hysterectomy, while maintaining a suitable distance from the placental upper margin¹⁴ 
• Delivery timeline for patients presenting with Placenta Accreta is varied in the literature and can depend on a variety of systemic and provider factors.  The Canadian Society of Obstetricians & Gynaecologists recommend delivery between 34-36 weeks¹¹, whereas the Royal College of Obstetricians & Gynaecologists recommend a 34-35 week window.¹³ 

Laceration / Organ Damage

There are inherent risks associated with intra-abdominal surgeries, including injury to key structures of the gastrointestinal and genitourinary tract.  These injuries are rare complications in Caesarean sections, but in all cases, it is appropriate to find the lesion/injury and repair it once the fetus has been safely delivered.  Intra-operative consultation with additional services like General Surgery and Urology can be helpful in navigating these challenging scenarios.  

References

1. Landesman R, Graber EA. Abdominovaginal delivery: Modification of the cesarean section operation to facilitate delivery of the impacted head. Am J Obstet Gynecol. 1984;148(6):707-710. doi:10.1016/0002-9378(84)90551-9 
2. Fong YF, Arulkumaran S. Breech extraction – An alternative method of delivering a deeply engaged head at cesarean section. Int J Gynecol Obstet. 1997;56(2):183-184. doi:10.1016/S0020-7292(96)02817-2 
3. Visconti F, Quaresima P, Rania E, et al. Difficult caesarean section: A literature review. Eur J Obstet Gynecol Reprod Biol. 2020;246:72-78. doi:10.1016/j.ejogrb.2019.12.026 
4. Waterfall H, Grivell RM, Dodd JM. Techniques for assisting difficult delivery at caesarean section. Cochrane Database Syst Rev. 2016;2016(1). doi:10.1002/14651858.CD004944.pub3 
5. Jeve Y, Navti O, Konje J. Comparison of techniques used to deliver a deeply impacted fetal head at full dilation: a systematic review and meta-analysis. BJOG An Int J Obstet Gynaecol. 2016;123(3):337-345. doi:10.1111/1471-0528.13593 
6. Pilliod RA, Caughey AB. Fetal Malpresentation and Malposition: Diagnosis and Management. Obstet Gynecol Clin North Am. 2017;44(4):631-643. doi:10.1016/j.ogc.2017.08.003 
7. Shoham(Schwartz) Z, Blickstein I, Zosmer A, Katz Z, Borenstein R. Transverse uterine incision for Cesarean delivery of the transverse-lying fetus. Eur J Obstet Gynecol Reprod Biol. 1989;32(2):67-70. doi:10.1016/0028-2243(89)90185-8 
8. Pelosi MA, Apuzzio J, Fricchione D, Gowda V V. The “intra-abdominal version technique” for delivery of transverse lie by low-segment cesarean section. Am J Obstet Gynecol. 1979;135(8):1009-1011. doi:10.1016/0002-9378(79)90726-9 
9. Cunningham FG, Leveno KJ, Bloom SL, Hauth JC, Rouse DJ, Spong CY. Williams Obstetrics. 23rd ed.; 2010. 
10. Wu S, Kocherginsky M, Hibbard JU. Abnormal placentation: Twenty-year analysis. Am J Obstet Gynecol. 2005;192(5 SPEC. ISS.):1458-1461. doi:10.1016/j.ajog.2004.12.074 
11. Hobson SR, Kingdom JC, Murji A, et al. No. 383-Screening, Diagnosis, and Management of Placenta Accreta Spectrum Disorders. J Obstet Gynaecol Canada. 2019;41(7):1035-1049. doi:10.1016/j.jogc.2018.12.004 
12. Collins SL, Alemdar B, van Beekhuizen HJ, et al. Evidence-based guidelines for the management of abnormally invasive placenta: recommendations from the International Society for Abnormally Invasive Placenta. Am J Obstet Gynecol. 2019;220(6):511-526. doi:10.1016/j.ajog.2019.02.054 
13. Placenta Praevia, Placenta Praevia Accreta and Vasa Praevia: Diagnosis and Management Green-Top Guideline No. 27.; 2011. 
14. Allen L, Jauniaux E, Hobson S, et al. FIGO consensus guidelines on placenta accreta spectrum disorders: Nonconservative surgical management. Int J Gynecol Obstet. 2018;140(3):281-290. doi:10.1002/ijgo.12409