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Opinii şi recomandări curente pentru utilizarea meşei în chirurgia ginecologică – review al literaturii
Background
Enhanced recovery after surgery (ERAS) is a concept used to include all the measures taken perioperatively to reduce morbidity and facilitate early recovery. It is a paradigm shift that involves multidisciplinary approach of the surgical patient and includes a number of measures that should optimize recovery and shorten hospital stay, evolving from good clinical practice to a standardized perioperative care program. ERAS guidelines have the aim of improving maternal and fetal outcome by increasing the safety of caesarean delivery, enhancing recovery and improving health outcomes(1).
ERAS concept started in 1990’s, in Denmark, with Professor Henrik Kehlet. He was one of the pioneers of the multimodal care approach for surgical patient. He published in 1997 a comprehensive approach of the surgical patient, taking into account pathophysiological changes and evidence-based effective measures to reduce surgical stress and morbidity(2). One of the first consensus reviews was published in 2005 in a nutrition journal by Fearon et al. (ERAS Study Group) and it approached enhanced recovery after colonic surgery; a protocol was developed afterward(3). In 2010, ERAS Society was officially registered in Sweden as a nonprofit medical society.
Although spontaneous spreading of principles between related surgical departments (colorectal and gynecology) occurred, they did not have the value of a guideline. Each surgical specialty has specific items to be implemented, so proactive implementation of ERAS principles in gynecologic oncology surgery proved to be necessary to achieve optimal outcomes(4). A systematic review of literature regarding ERAS principles in gynecologic oncology surgery underlined the significant improved outcomes and patients satisfaction, reduction of costs and length of admission(5). An audit of ERAS implementation process results was published in 2018. Patients outcomes, length of hospital admission and economic impact were assessed. ERAS implementation results showed shorter hospital stay, low complications rate, and significant cost savings(6).
Antenatal and preoperative measures
The antenatal approach for ERAS concept should start between 10 and 20 weeks of gestation(1).
The patient should receive preadmission information and be managed by a multidisciplinary team. Education, counselling and management of maternal-associated morbidity should be the initial part of ERAS for future caesarean delivery patients. This is the case of the patients who already have an indication of delivery by caesarean section, but also for the complex cases where an unplanned caesarean delivery might be anticipated.
Counselling and antenatal information
Adequate and updated information regarding both possibilities, either vaginal or caesarean section delivery, should be provided to the pregnant patient and to her partner during antenatal visits. The discussion should be documented, as well as the type of recommended delivery, timing of delivery, details regarding the provider of information, and the acceptance and level of understanding of the patient. The patients opting for vaginal delivery should be informed also of the possibility of emergency caesarean delivery, especially because usually the time for consenting before an emergency caesarean section is seldom short. The information will be reiterated before starting the procedure, and an informed consent will be signed by the patient.
The details that should be discussed antenatally include the indication of caesarean delivery, the type of abdominal incision used, a short description of the procedure, with duration of surgery and median length of hospital stay, possible complications that could occur, postoperative risk of thromboembolism, prophylactic use of compressive stockings and prophylactic low molecular weight heparin, the plan of oral solid food and fluids intake pre- and postoperatively and the locations of mother and baby after delivery.
For emergency situations, the patient should receive essential information regarding the surgical procedure and the indication that rushed the decision from the obstetrician, as well as information regarding the type of anesthesia from on duty anesthesiologist. A discussion with the neonatologist should be useful when the indication for caesarean section is related to fetal concerns(1).
Patients requiring caesarean section delivery without medical indication, after failure of counseling them for vaginal delivery, should be informed appropriately regarding the risks such as intraoperative organ injury, bleeding, postoperative infection or thrombosis, as well as pain and delayed ambulation(7-10). Late risks for the following pregnancies, like uterine rupture or placenta accreta spectrum, should also be acknowledged(11,12).
The adjustment of clinical factors that might interfere with rapid recovery after caesarean section (CS) is also important. Frequent comorbidities, such as obesity, anemia, hypertension and diabetes mellitus, have to be taken into account(13). They require preoperative optimization for an improved surgical outcome. Maternal obesity preexisting to pregnancy increases the risks of complication during pregnancy, CS delivery and after surgery(14-16). The risks of maternal and fetal morbidity and of CS delivery are increased, as well by maternal hypertension, either chronic preexisting or pregnancy-induced forms; it should therefore be managed accordingly during pregnancy, with the aim of preventing severe hypertension and prolonging gestation to reduce fetal prematurity-associated morbidity(17). Diabetes mellitus should be treated before and during pregnancy because of associated increased risks of fetal anomalies, abortion, macrosomia, shoulder dystocia, but also preeclampsia and CS delivery(18-20). Almost 40% of pregnancies are complicated by anemia (Hb level under 11 g/dl) according to WHO data. Romania had a prevalence of about 27% in 2016(21,22). Anemia should be corrected during the antenatal period to reduce the risks of perioperative morbidity, transfusion rate and fetal adverse outcomes(23,24). Smoking cessation during pregnancy should also be strongly recommended.
Preoperative measures
The preoperative period refers usually to a series of measures concentrated between 30 and 60 minutes before CS delivery procedure starts, excepting for emergency unscheduled CS, when this period is much reduced.
Anesthetic medication
Preoperative anesthetic medication has the aim of reducing aspiration pneumonitis, which occurs usually in patients requiring general anesthesia, including CS delivery patients with locoregional anesthesia who need conversion to general anesthesia. The medication which proved to be effective and safe includes antagonists of H2 histamine receptors and antacids that lower the risk of aspiration pneumonitis(25). There is no proven benefit for premedication with sedatives before CS delivery. Fetal and maternal side effects presumed to be related to the use of sedative premedication, from fetal hypotonia or floppy baby syndrome, lower Apgar score, to impaired maternal psychomotor function, were not proved in several trials(26-28). However, routine use of sedatives in the preoperative setting before CS delivery should be avoided(1).
Bowel preparation
Once routinely used before surgical procedures, especially colorectal surgery, bowel preparation, either with oral laxatives or with enema, has been proved ineffective in lowering perioperative morbidity (site infection, anastomotic leak)(29). Hence, oral or mechanical bowel preparation before caesarean section delivery should not be recommended(1).
Preoperative alimentation
Because of the presumed risks of aspiration pneumonitis with preoperative nutrition, fasting was usually advocated before any surgical procedure, starting at least 6 hours before surgery or even more. Current evidence failed to demonstrate an increased risk of aspiration or related morbidity in patients who had oral fluids, compared with traditional fasting policy (“nil by mouth from midnight”)(30). The present ERAS guidelines published in The American Journal of Obstetrics and Gynecology advise patients to drink clear fluids up to 2 hours before surgery and have a light meal up to 6 hours before surgery, based on current existing evidence(1,31,32).
Oral carbohydrate supplements have been evaluated for their role in improving outcomes when administered up to 2 hours before surgery. The exceptions are the patients with diabetes mellitus. Most trials did not report a clear benefit in enhanced recovery of the surgical patient, but there were no safety concerns revealed. A Cochrane review of literature from 2014 about carbohydrate supplements before planned surgery revealed only a small reduction in the length of hospital stay, with no impact on postoperative complication rates(33). The evidence for recommending oral carbohydrate fluid intake up to 2 hours before caesarean section in non-diabetic patients is therefore low(1).
Antibiotic prophylaxis
Preoperative antibiotic prophylaxis should be administered between 30 to 60 minutes before skin incision. The risk of postoperative infection is different depending on the type of surgery, emergent or elective. Elective CS delivery has a lower risk of postoperative infection morbidity because the type of wound is considered clean (class I), while emergency CS delivery is considered rather clean-contaminated (class II) or sometimes when frank intrauterine infection is proved even contaminated (class III)(34,35). Microbial profile is also different between elective surgery (skin flora) and emergency surgery in a patient in labor with ruptured membranes (skin and vaginal flora).
For elective CS delivery, the risk of infection is lower and antibiotic prophylaxis with a narrow-spectrum first generation cephalosporin (such as cefazolin) is the standard of care(36,37). Although initial protocols were limiting fetal exposure to antibiotic by administering it after cord clamping, systematic reviews revealed significantly increased efficacy when the administration was offered before skin incision. Current standard recommendation is to administer the prophylactic antibiotic 30 to 60 minutes before skin incision(38).
For emergency CS delivery (in labor with ruptured membranes), the same principles mentioned before are valid with some remarks. First, the microbial spectrum is different and includes vaginal flora apart from the skin bacteria; adding antibiotics to broaden the spectrum (azithromycin) has been shown, in several trials, to significantly reduce postoperative infection rate(39-41). Secondly, in patients in labor or with ruptured membranes, there is a clear communication of the vaginal flora with upper genital tract, and antimicrobial vaginal preparation with povidone-iodine has been proved effective in multiple studies(42).
Local antiseptic measures
As already mentioned, vaginal preparation with povidone iodine or chlorhexidine before CS delivery in labor or with ruptured membranes decreases the incidence of postoperative infectious morbidity, especially endometritis, from 8.7% to a rate of only 3.8%(42).
When evaluating the risks of surgical site infection depending on the antiseptic used for patient skin cleansing, although a Cochrane meta-analysis was inconclusive when comparing povidone iodine with chlorhexidine-alcohol, recent studies tend to favor chlorhexidine for reduced rates of surgical site infections(43-45).
Concerning the substances used for surgical hand antisepsis, a meta-analysis failed to show any significant difference between various antiseptic solutions or different alcohol rubs with different antiseptic ingredients or the role of brushes or nail picks; the evidence found was of low quality overall(46).
The administration of topical antibiotics to promote wound healing and reduce surgical site infections (SSI) seems to reduce the rate of SSI when compared to no local antibiotics strategy, with moderate quality evidence, but with no conclusion regarding the developing of antibiotic resistance and allergic contact dermatitis(47).
Wound dressing at the end of surgery is a generalized practice that was analyzed in a Cochrane meta-analysis regarding the impact on SSI. The evidence was of low quality, with conclusions leaving wound dressing to patient preference and to dressing costs(48).
In conclusion, regarding antibiotic and antiseptic prophylaxis, first-generation cephalosporin should be administered intravenously before skin incision within 60 minutes, with the addition of azithromycin for CS done in labor or with ruptured membranes. Povidone iodine should be recommended for vaginal antisepsis before CS delivery in patients with ruptured membranes or in labor. Chlorhexidine-alcohol provides better protection against SSI when used for abdominal skin disinfection compared to povidone iodine(35).
Peri- and intraoperative measures
Prevention of intraoperative hypothermia
Perioperative hypothermia in the setting of CS delivery under spinal anesthesia is a common event due to multiple predisposing factors involved. Spinal anesthesia impairs temperature autoregulation by altering vasomotor response and inhibiting shivering. Also, spinal anesthesia blocks the input from peripheral cold sensorial receptors, and intrathecal morphine derivatives for postoperative pain control increase the degree of hypothermia(49). Hypothermia is frequent in patients having CS delivery, some trials citing a prevalence of up to 90% of patients without any active warming protection measures(50). Perioperative hypothermia was associated with adverse outcomes in multiple trials, including increased length of hospital stay, increased blood loss and surgical site infection rates or myocardial ischemia(51,52). The neonate is also adversely affected by the hypothermia, revealed by low Apgar scores or umbilical pH(53). Adequate temperature monitoring of CS patients is difficult and unreliable using conventional strategies and often monitoring is not done at all(54,55). Modern techniques of temperature monitoring are under evaluation(56). The prevention of inadvertent perioperative hypothermia was obtained combining different strategies like using intravenous warmed fluids, forced-air warming or increasing the operating room temperature. All the aforementioned measures were found significantly effective and are recommended to reduce perioperative hypothermia(35,57-59).
Anesthetic management
Regional anesthesia or neuraxial techniques are the preferred methods used for CS delivery when compared with general anesthesia because of the reduced rates of maternal deaths due to anesthesia and to reduced postoperative sedation(60,61). However, a systematic review failed to identify any significant differences in major adverse maternal or fetal outcomes between regional and general anesthesia, possible due to inadequate power to identify rare events like death or other severe morbidity(62). When spinal and epidural anesthesia were compared in a meta-analysis, spinal anesthesia enabled earlier start of surgery, but having more hypotensive events, without significant differences regarding failure of procedure or side-effects like headache, nausea and vomiting or other postoperative complications(63). When compared with general anesthesia, regional anesthesia is the method of choice for CS delivery.
Surgical technique aspects
Although CS is one of the most frequent surgical procedures, a consensus regarding the best technique on evidence-based data is still lacking. Different authors have multiple variations of the technique, which makes it difficult sometimes to reach valid conclusions. Nevertheless, there are multiple randomized trials and systematic reviews assessing different steps of the procedure.
Surgical skin incision, traditionally favored, is low-transverse Pfannenstiel. The recently described Joel-Cohen technique consists in transversely sharply incising the subcutaneous fat and rectus abdominis fascia only in the midline, digitally expansion of rectus fascia laterally and separation of rectus muscles in the midline by pulling. Peritoneum is entered bluntly with the fingers and expanded cranio-caudally.
The development of the bladder flap after incision of vesical-uterine peritoneal fold does not bring any advantage and should be abandoned(64,65). Sharp incision in the midline of the uterine segment until membranes are bulging should be bluntly expanded by pulling with fingers cranio-caudally. This approach is followed apparently by less blood loss and less lateral extensions in the uterine pedicles(66,67). The Joel-Cohen technique based mainly on blunt dissection is associated with less blood loss, shorter operating time and faster postoperative recovery(68-70).
Closing the hysterotomy incision can be accomplished in several ways. A Cochrane meta-analysis failed to identify any significant difference between single versus double layer closure, when febrile morbidity and the risk of blood transfusion were analyzed(71). However, a higher risk of uterine rupture for single layer closure patients in a subsequent pregnancy was revealed in several trials(72,73). Locked single layer closure of uterine hysterotomy incision rather than unlocked was associated with a higher risk of rupture during trial of labor in patients with CS scar(74). There were no significant differences identified when absorbable or delayed absorbable suture were used for uterine closure.
Visceral or parietal peritoneum closure did not add any benefit for the patient and its omission shortened the operative time(75-77). The re-approximation of rectus muscles should be discouraged because it does not bring any advantage for the patient(78). Rectus fascia should be closed using running absorbable suture(79). The subcutaneous fat tissue should be closed with absorbable stitches, interrupted or continuously, in patients with more than 2 cm layer thickness to reduce delayed healing and wound infection rate(79-82). Subcutaneous drain placement does not bring any proven benefit for wound healing process.
Skin closure can be done with subcuticular absorbable stitches or using staples. A Cochrane meta-analysis from 2012 did not show any difference between subcuticular suture and non-absorbable staples regarding wound infection rate or other wound complications, pain or cosmesis. Skin separation rate was slightly higher in staple closure population, especially when staples were removed before four days postpartum(83-85). A randomized trial from 2014 comparing outcomes of subcuticular suture closure and staple closure revealed a significantly higher skin separation rate with staples, while suture closure decreased complications with over 50%(86). Other randomized trials failed to prove any significant difference regarding healing outcome between the two methods of skin closure, even in obese patients(87,88). Overall, subcuticular skin suturing should be preferred over closing with staples(35).
Perioperative fluid balance
Fluid management is important to prevent depletion as well as overloading to achieve optimal recovery. Maintaining optimal tissue perfusion by an adequate intravascular blood volume improves fetal oxygenation and outcomes, as well as maternal postoperative recovery. Fluid overload should be avoided as well, because of the risks of maternal pulmonary edema. The prevention of spinal anesthesia induced hypotension is achieved with a loading regimen based on a crystalloid solution preload and phenylephrine infusion, that proved to be beneficial for mother and fetus(89-91). Perioperative fluid balance to avoid overloading should be judiciously analyzed, especially in hypertensive pregnant patients, but also in normotensive parturients; acute pulmonary edema leads to significant morbidity and mortality in pregnancy(92). In conclusion, the maintenance of euvolemia with cristaloids and vasopressors is important for improving fetal and maternal outcome at caesarean delivery.
Enhanced recovery after surgery is a concept that gained popularity because of the need to standardize surgical practice that was often much more heterogenous at the individual level and lacking evidence-based stepwise approach of the perioperative medical care and intraoperative technique. Caesarean delivery is the most common surgery in many developed countries in the world, with a steady rise from 4.5% in 1970 to 32% in 2015 in the US, while in Eastern Europe in 2015 the rates cited were around 27%, with highest rates in Latin America and Caribbean, of around 44%(93). Even higher rates of caesarean section can be found in several urban areas in Romania, so a standardized pathway for CS delivery is an important step in reducing associated morbidity and costs. Therefore, implementing evidence-based measures in caesarean section delivery to improve maternal and neonatal outcomes and increase efficacy and effectiveness of the medical process is an important step in optimizing the healthcare activity.
Conflict of interests: The authors declare no conflict of interests.
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