163x Filetype PDF File size 0.30 MB Source: www.thieme-connect.com
Published online: 2020-02-06 THIEME S98 Precision Surgery in Obstetrics and Gynecology Classical Cesarean Section 1 AmanoKan,MD,PhD 1Department of Obstetrics and Gynecology, Center for Perinatal Address for correspondence Amano Kan, MD, PhD, Department of Medicine,KitasatoUniversitySchoolofMedicine,YoshidaObstetrics Obstetrics and Gynecology, Center for Perinatal Medicine, Kitasato and Gynecology Clinic, Tokyo, Japan University School of Medicine, Yoshida Obstetrics and Gynecology Clinic, 251-0861 5061-4 Ohba Fujisawa-City, Kanagawa, Japan Surg J 2020;6(suppl S2):S98–S103. (e-mail: kanamano0101@gmail.com). Abstract Cesarean section is the most common surgery in obstetrics. Several techniques are proposed according to the indication and the degree of urgency. Usually laparotomy followedbyhysterotomywithalowtransverseincisionispreferable.However,incases inwhichitisdifficulttoaccesstheloweruterinesegment,suchasthatinpretermlabor, Keywords dense adhesion, placenta previa/accrete a vertical hysterotomy (classical cesarean ► cesarean section section)maybeneeded.Althoughasmoothandgentledeliveryofthefetusispossible ► vertical uterine through the vertical incision, uterine closure is technically difficult. To decrease the incision risks of hemorrhage and adhesion, a speedy and skillful technique is mandatory. The ► classical cesarean mostserious risk of vertical incision in the contractile corpus is uterine rupture in the section subsequentpregnancy.Therefore,cases of prior classical cesarean section are contra- ► uterine rupture indicated for trial of labor after cesarean section. Cesareansectionisthemostfrequentobstetricoperationthatis Indications for Classical Cesarean Section performedincaseswhenavaginaldeliverywouldputthefetus Preterm Labor ormotheratrisk.Severalproceduresareoffereddependingon Since the poorly developed lower uterine segment provides theindicationandthedegreeofurgency.Afterlaparotomy,the inadequate space for the manipulations required for fetal uterus can be incised by a variety of techniques, usually low delivery, especially in cases prior to 30 weeks of gestation, transverseuterineincisionisselected(►Fig.1).Attimes,alow with nonreassuring fetal status or inevitable preterm labor transverse hysterotomy is selected but provides inadequate arecandidatesfortheclassicalcesareansection.Ininstances roomfordelivery. Insuch cases incision is extended such as J- when the fetus is very small, especially in case of a breech extension, U-extension, and T-extension. However, in some presentation,thesmallfetalheadmaybecomeentrappedby cases, where the low transverse incision is arduous, a midline the small low transverse incision space and uterine contrac- vertical incision (classical cesarean section) is considered. tions, therefore classical cesarean section is desirable to prevent the fetal risk of intracranial hemorrhage. The risks Surgical Steps of neonatal mortality and morbidity may be decreased by classical cesarean section in some cases of preterm labor (►Table 1). 1. Midline vertical incision for laparotomy ↓ Fetal Indications 2. Hysterotomybymidlinevertical incision abovethe Transverselieofalargefetus,especiallyifthemembranesare lower segment ruptured and the shoulder is impacted in the birth canal ↓ necessitates a classical incision. A fetus presenting as a back- 3. Delivery of the fetus/placenta downtransverselieisparticularlydifficulttodeliverthrough ↓ a low transverse incision. 4. Uterine repair Malformedfetussuchasconjoinedtwins,sacrococcygeal ↓ teratoma, macrocrania, myelomeningocele is difficult to 5. Abdominal closure deliver gently through a low transverse incision. DOI https://doi.org/ Copyright © 2020 by Thieme Medical 10.1055/s-0039-3402072. Publishers, Inc., 333 Seventh Avenue, ISSN 2378-5128. NewYork, NY 10001, USA. Tel: +1(212) 760-0888. Classical Cesarean Section Kan S99 Fig. 1 Variety of incisions for hysterotomy. (A) Low transverse. (B)Lowvertical.(C) Low transverse with T-extension in the midline. (D)Low transverse with J-extension. (E) Low transverse with U-extension. (F)Hightransverse.(G)Fundaltransverse.(H) Midline vertical (classical incision). (Reproduced with permission of Amano K. In: Hiramatsu Y, Konishi I, Sakuragi N, Takeda S, eds. Mastering the Essential Surgical Procedures OGS NOW, No.3. Cesarean Section. (Japanese). Tokyo: Medical View; 2010:42–47. Copyright © Medical View). Table 1 Indications for classic cesarean section Placenta Previa Preterm labor Breech, transverse lie Incaseofplacentaprevia,placentalincisionshouldbeavoided, (30 wk) especially if the placenta accrete is suspected from prenatal Nonreassuring fetal status ultrasonographyandintraoperativeinspectionoftheengorged Difficult to Serious adhesion around the uterine superficial vessels, a classical incision or a fundal access the vesicouterine space transverse incision is advisable. If placenta accrete/increta is lower segment Morbidobesity suspected,auterineincisionisperformedwhilekeepingaway Uterine Myomauteri from the placenta and after delivering the fetus, the cord is abnormality Anomalousuteri ligated and cut, and the placenta is left in situ. The uterine incisionissuturedbyacontinuousrunninglockingsuture,and Cervical carcinoma a hysterectomy is immediately performed. Fetal indication Malformation (macrocrania, sacrococcygeal teratoma, Procedure of the Classical Cesarean Section myelomeningocele, conjoined twins) Transverse lie Abdominal Incision Usually a midline vertical incision is chosen for laparotomy. A vertical infraumbilical incision provides quick entry to Uterine Abnormality shorten the incision-to-delivery interval. Moreover, this inci- In cases of an anomalous uterus with a hypoplastic cervix, sion has minimal blood loss, provides superior access to the myoma uteri, or invasive cervical cancer a low transverse upper abdomen and generous operating room, and offers incision is not indicated. flexibility for easy wound extension if greater space or access isneeded.Themaindisadvantagesarepoorercosmeticresults, Difficult Access to the Uterine Lower higher rates of fascial dehiscence or incisional hernia, and Segment greater postoperative pain compared with a Pfannenstiel transverse incision. Whenitisveryhardtoaccesstheuterinelowersegment in An infraumbilical midline vertical incision begins 2 to cases with dense adhesion, or morbid obesity, incision into 3cmabovethesuperiormarginofthesymphysisandshould the vesicouterine peritoneum and separating the bladder is be of sufficient length (12–14cm) to allow fetal delivery difficult, indicating a classical cesarean section. without difficulty. Sharp or electrosurgical dissection is The Surgery Journal Vol. 6 Suppl. S2/2020 S100 Classical Cesarean Section Kan performed to the anterior rectus sheath. Fascial incision is extended superiorly and inferiorly with scissors or scalpel. The rectus abdominis and pyramidalis muscles are subse- quently separated, and the peritoneum is carefully opened. Before hysterotomy, the surgeon should palpate the fundus and adnexa to identify the degree of uterine rotation. The uterus may be dextrorotated due to the proximity of the sigmoid colon so that the left round ligament is more anterior and closer to the midline. Uterine Incision Amidlinevertical uterine incision in the contractile corpus is carefully initiated with a scalpel until the membranes appeared, and when the uterus is entered, the incision site is openedwithfingerswideenoughtomakeanadequatespaceto deliver the fetus. If the placenta is encountered in the incision line, the placenta is torn off and membranes are ruptured as quickly as possible to avoid severe fetal hemorrhage. As the incisionisopened,numerouslargevesselsthatbleedprofusely are commonlyencounteredwithinthemyometrium. Aspeedyandskillful technique is mandatory. Fig. 2 Closure of the firstlayer.TextA:Closingthefirst layer by Alowvertical incision is made parallel to the longitudinal intermittentsuturesincludesthedeepmyometrialedgewithminimal decidua. (Reproduced with permission of Amano K. In: Hiramatsu Y, axis of the uterus in the midline with carebeing taken to stay KonishiI,SakuragiN,TakedaS,eds.MasteringtheEssentialSurgical belowthecontractileportionoftheuterusandwithinthethin Procedures OGS NOW, No.3. Cesarean Section. (Japanese). Tokyo: lower uterine segment. Studies have shown that there is no Medical View; 2010:42–47. Copyright © Medical View). significant increased risk of uterine rupture in patients with this type of incision compared with low transverse incision. Delivery of the Fetus and Placenta The main principle to remember is that the dead space After the membranes are ruptured, the fetus will be deliv- needs to be obliterated to achieve hemostasis and it ered easily compared with cases with a low transverse reduces the chance of hematoma formation. The first layer incision.Theumbilicalcordshouldbeligatedandcut.Fundal is closed with interrupted sutures (#1 Coated VICRIL PLUS, massagemaybeginassoonasthefetusisdeliveredtohasten ETICON Inc.) with decidual exclusion to avoid endometrial placental separation, and the placenta is manually removed. inversion at the scar site, because this may be the cause of Immediatelyafterdeliveryoftheplacenta,theuterinecavity incomplete scar healing (►Fig. 2). Concerns have been is suctioned and wiped out with a gauze sponge to remove expressed that sutures through the decidua may lead to the remaining membranes, vernix, and clots. endometriosis or adenomyosis in the hysterotomy scar, After birth, to facilitate the uterine contraction, an intra- however, this is rare. The second layer is also closed with venous infusion of 10 units oxytocin in 1L of crystalloid interrupted sutures, and the final layer is closed with solution may be begun. Second-line agents are ergot alka- continuous locking sutures or figure-of-eight sutures loids, and the use of tranexamic acid has recently been (►Figs. 3, 4). described to lower blood loss during cesarean delivery. After closure of the incision, an adhesion barrier patch, There is insufficient evidence of mechanical or finger such as SEPRAFILM, KAKEN Inc. or GYNECARE INTERCEED, dilatation of the cervix during nonlabor cesarean section ETICHON Inc. is applied. to reduce postoperative morbidity such as infection rates from potential hematometra. AbdominalClosure Prior toabdominalclosure,allsurgicalspongesareremoved, Uterine Repair andtheparacolicguttersandcul-de-sacaregentlysuctioned of blood and amniotic fluid. The uterine contraction, hemo- Afterremovaloftheplacenta,theuterusisliftedthroughthe stasis of the incision, and the aspect of the adnexa are then incision onto the abdominal wall. Although some clinicians confirmed. After gauze and instrument counts are found to prefer to avoid such exteriorization, there are often benefits be correct, the abdominal cavity is irrigated with warmed that outweigh the disadvantages. saline. For incision closure, it is helpful to have an assistant Abdominal incisions are closed in layers. Peritoneum compress the uterus on each side of the wound toward the fasciaisclosedwithinterruptedsutureorcontinuoussuture, midlineaseachstichisplacedtoachievegoodapproximation. and subcutaneous tissue is approximated with interrupted Because the classical incisions are much thicker, they are suture.Skinisclosedwithstaplersand/orinterruptedrelax- normally repaired in three layers. ation sutures. The Surgery Journal Vol. 6 Suppl. S2/2020 Classical Cesarean Section Kan S101 Table 2 Merits and demerits for classical cesarean section Merits Deliver the fetus without difficulty Avoid bladder injury Extend incision without lacerating uterine arteries Demerits Increased blood loss Difficulty of uterine closure Increased complications of infection Postoperative adhesion Subsequent uterine rupture or uterine scar dehiscence (low vertical; n¼53, classical; n¼134) versus low trans- verse incision in preterm cesarean section between 23 and 34weeksofgestation.Afteradjustingforconfounders,there was no significant difference in the incision-to-delivery interval between the two types of incisions. However, the Fig.3 Closureofthesecondlayer.TextB:Thesecondlayercompletesthe risk for maternal transfusionwashigheramongthosewitha myometrial approximation and hemostasis. The dead space needs to be vertical incision. The incision type was not associated with obliterated. (Reproduced with permission of Amano K. In: Hiramatsu Y, any neonatal outcomes including intracranial hemorrhage, Konishi I, Sakuragi N, Takeda S, eds. Mastering the Essential Surgical low Apgar score, or neonatal mortality. The need for rapid ProceduresOGSNOW,No.3.CesareanSection.(Japanese).Tokyo:Medical delivery is not justified by Luthra et als’ findings, and this View; 2010:42–47. Copyright © Medical View). shouldnolongerbeconsideredasanindicationforavertical Benefits and Risk of Classical Incision incisioninthepretermpopulation.Furtherstudiesincluding the effect on long-term outcome are warranted (►Table 2). Benefits Thefetus can be delivered quickly and gently with minimal Risks risk of forcing delivery which may result in intracranial hemorrhage in a preterm case. Intraoperative, Postoperative Risk 1 Luthra et al compared the uterine incision-to-delivery Asaclassical uterine incision is made by incising the uterus intervalandneonatalandmaternalcomplicationsinvertical parallel to the longitudinal axis of the uterus through the Fig. 4 Closure of the third layer. (A)Zsuture.(B) Continuous suture, figure-of-eight suture. (Reproduced with permission of Amano K. In: Hiramatsu Y, Konishi I, Sakuragi N, Takeda S, eds. Mastering the Essential Surgical Procedures OGS NOW, No.3. Cesarean Section. (Japanese). Tokyo: Medical View; 2010:42–47. Copyright © Medical View). The Surgery Journal Vol. 6 Suppl. S2/2020
no reviews yet
Please Login to review.