Dermatology: Practical and Conceptual Original Article | Dermatol Pract Concept. 2023;13(3):e2023175 1 Can Stria Gravidarum Predict Surgical Fluid Loss in Cesarean Section? Seyma Banu Arslanca1, Ozgur Sahin2, Ugurkan Erkayıran3, Zehra Ozturk Basarır4, Tufan Arslanca4 1 Department of Obstetrics and Gynecology, Etlik Zübeyde Hanım Maternity and Women’s Health Teaching and Research Hospital, Ankara, Turkey 2 Department of Obstetrics and Gynecology, Canakkale State Hospital, Canakkale Turkey 3 Department of Obstetrics and Gynecology, Sutcu Imam University, Faculty of Medicine, Kahramanmaras, Turkey 4 Department of Gynecologic Oncology, Ankara City Hospital, University of Health Sciences, Ankara, Turkey Key words: Stria gravidarum, surgical fluid loss, cesarean section, Davey score Citation: Arslanca SB, Sahin O, Erkayıran U, Basarır ZO, Arslanca T. Can Stria Gravidarum Predict Surgical Fluid Loss in Cesarean Section? Dermatol Pract Concept. 2023;13(3):e2023175. DOI: https://doi.org/10.5826/dpc.1303a175 Accepted: November 7, 2022; Published: July 2023 Copyright: ©2023 Arslanca et al. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original authors and source are credited. Funding: None. Competing Interests: None. Authorship: All authors have contributed significantly to this publication. Corresponding Author: Tufan Arslanca, Department of Gynecologic Oncology, Ankara City Hospital, University of Health Sciences, Ankara, Turkey. ORCID:0000-0001-9686-1603 E-mail: drtufanarslanca@hotmail.com Introduction: Alterations in collagen subtypes and matrix can potentially cause fluid loss in surgery which is important in terms of liquid loss. Objectives: The study aimed to analyze stria gravidarum (SG) and its severity in pregnant women who had undergone cesarean section (CS) and to evaluate surgical fluid loss (SFL) that occurred during CS operation. Methods: The research was designed as a prospective clinical cohort study to compare the amount of SFL in the second cesarean section with the severity of SG at 34-37 weeks pregnant (N 308). The severity of SG was evaluated in the preoperative period using the Davey scoring. All patients were de- fined none, mild stria and severe stria. The SFL was calculated by weighing the pre-and post-operative weights of the sponges. Results: The weight gain (P = 0.008) and body mass index (BMI, P = 0.017) gradually increased to- ward severe SG. In correlation analysis of SFL, a positive correlation was found with Davey (r=0.791; P = 0.0001), weight gained during pregnancy (r=0.328; P = 0.0001), BMI (r=0.453; P = 0.001) and newborn weight (r=0.139; P = 0.003). In the receiver operating characteristic for the predictability of SG severity on SFL, severe SG showed a potential for SFL with 95.1% specificity and 93.2% sensitiv- ity at 791 cut-offs (area under the curve:0.987; P = 0.00001; 95% confidence interval: 0.977-0.997). ABSTRACT 2 Original Article | Dermatol Pract Concept. 2023;13(3):e2023175 Introduction As a result of immunological, metabolic, endocrine, and vascular changes that occur during pregnancy, various phys- iological and pathological processes occur in the skin and skin appendages of the pregnant woman [1,2]. Among the physiological skin changes seen in pregnant women such as weight gain [3], stria gravidarum (SG) is considered to be the most common skin change [4]. After birth, the skin color is characterized by bands that turn into hypopigmented, atro- phic lines, and appear on the abdomen, thighs, distal fem- oral areas, inguinal region, and breasts after an average of 24 weeks of gestation [2,5]. These lesions, whose exact cause is unknown, are thought to develop as a result of connective tissue changes such as a decrease in the amount of elastin and fibrillin in the dermis [6,7]. After birth, it is less visible with a pale and cream-colored, atrophic appearance over time, but it does not disappear completely [8,9]. Although striae are not a serious condition that will risk health, they can cause complaints such as itching and burn on the skin, and these physical changes can cause serious anx- iety in pregnant women [10]. Local retinoic acids, glycolic acid, and vitamin C may be beneficial after pregnancy [11]. Benefiting from these supplements is one of the strongest in- dications of how critical a collagen deficiency or disorder plays in SG [12,14]. Collagen is not only the crucial com- ponent of the extracellular-matrix, maintaining the dermis structure but also an important molecule for coagulation systems [15-17]. Although the formation of the vascular tube takes place in a polymerized 3D collagen lattice, endothe- lial cells cannot be organized into capillary-like structures on a hard plastic surface [18]. It is unclear how damage to the collagen matrix triggers endothelial cell organization in a vascular network and what factor might be involved. Cell- to-cell interactions in the vascular structure are essential for the endothelial cell organization to transform into a luminal structure and may be associated with SG due to altered col- lagen fibers and a collagen matrix [19]. Objectives We acknowledged that alterations in collagen subtypes and matrix can potentially cause fluid loss and this issue has not been investigated in terms of SG and its severity. The pres- ent study aimed to analyze the SG data and its severity in pregnant women who had undergone cesarean section (CS) and to evaluate the relationship of these values with the surgical fluid loss (SFL) that occurred during CS operation. Thus, we focused to understand the relationship between the severity of SG and the amount of SFL during the CS. Methods Study Design The study was designed as a prospective clinical cohort study to compare the amount of SFL in the second cesarean section with the severity of SG in 34-37 weeks pregnant women. The study included healthy pregnant women over the age of 18 who gave birth to a single newborn in their second CS at the Medical Center between 2020 and 2022. The study was ap- proved by the review board of the institution (14.10.2022- 07-363) and conducted following the Helsinki declaration, a set of ethical principles regarding human experimentation. All the participants read and signed the informed consent about the study. Study Participants All pregnant women who attended the hospital and were scheduled for CS were invited to enroll in the study. Inclu- sion criteria were to be admitted for the second cesarean sec- tion with the severity of SG in 34-37 weeks pregnant women who had a history of only one cesarean section. Reluctance to participate in the study, not meeting the admission crite- ria, having a chronic disease, and having any complications in the previous cesarean section were accepted as exclusion criteria. In addition to 7 women who were not willing to participate in the study for various personal reasons, 42 peo- ple with a midline incision, suspected preoperative placenta accreta, using corticosteroids, history of abdominopelvic surgery and/or wound infection, endometriosis or pelvic in- flammatory disease were excluded from the study. Stria-Davey Scoring and Groups For study planning, one of the researchers consulted all eli- gible participants to obtain detailed anamnesis; CS history, age, body mass index, gestational age, parity, previous mis- carriage, etc. The severity of SG was evaluated in the pre- operative period using the four body regions (abdominal, hip, hip, and breast) where SG is most common and using Conclusions: The SG severity and SFL showed a very strong relationship, which was a very important finding that would affect the approach of the surgeons to the patients with SG in terms of fluid loss in CS. Original Article | Dermatol Pract Concept. 2023;13(3):e2023175 3 the Davey scoring system. The abdomen was divided into 4-quadrants concerning a line drawn horizontally from the midline and the navel, and each quadrant was given a score: score 0=clear skin, score 1=moderate (1–3), and score 2=many striae (4 and more). According to this calculation, the scores of all four quadrants were added together to ob- tain the total, and patients with none (score 0) were defined as the group I, mild (score1-2) were defined as II and severe (score 3-8) were defined as III. C/S Operation and SFL Amount All CS included in the study was performed and the data were recorded by two experienced residents and blinded to the results of the Davey score assessment. Surgeons were asked to measure and report the amount of SFL after per- forming the surgery. They calculated the amount of SFL by weighing the pre-and post-operative weights of the sponges we used in the cesarean section in the operating room and looking at the hemoglobin difference. We used sponges af- ter the delivery of the baby and placenta and thus, excluded amnion and bleeding due to c/s. In addition, the amount of blood measured with sponge was considered to be insig- nificant, since there was no difference at preoperative and postoperative values of the hemoglobin and hematocrit. In this way, the weight difference between sponges reflects the amount of SFL. Statistical Analysis After the data were collected, they were turned into an excel spreadsheet and the data were transferred to SPSS©Statistics v22 (IBM© Corp.) and analyzed with proper methods. While quantitative data were presented as mean and standard devi- ation, qualitative data were presented as frequency and per- centage. The Mann-Whitney test compared the Skewed data while the unpaired t-test evaluated the normally distributed quantitative data such as SFL amount. Categorical data were compared using the chi-square test or Fisher exact test if ap- propriate. Correlation analysis of the amount of SFL and severity was performed in the groups determined according to the Davey score. In addition, we performed a stepwise lin- ear regression model for predictors. The receiver operating characteristics (ROC) curve was constructed to determine the best cut-off value for the amount of SFL and SG sever- ity diagnostic fit. The best cut-off in the ROC curve has the highest true positive rate along with the lowest false positive rate. A P-value less than 0.05 was considered significant. Results Three hundred fifty-seven women were evaluated to partic- ipate and 49 cases did not join the present study due to not meeting the inclusion/exclusion criteria. The 308 pregnant were defined by Davey score into three subgroups: group-I included 71 as none, group II included 107 as mild, and group III included 130 women as severe. The mean age was 28.7± 6.07 years and did not differ for groups (P = 0.566). The weight gain (P = 0.008) and body mass index (BMI, P = 0.017) gradually increased toward severe SG. Hemoglobin (pre/postoperative), platelet, PT, aPTT, AST, ALT, BUN, creatinine, and fibrinogen were similar for groups. There was no significant difference in the baseline characteristics of both study groups, as seen in Table 1. In the correlation analysis performed with the amount of SFL, a positive correlation was found with Davey (r=0.791; P = 0.0001), weight gained during pregnancy (r=0.328; P = 0.0001), BMI (r=0.453; P = 0.001) and newborn weight (r=0.139; P = 0.003). Other parameters we analyzed did not show a significant relationship with the SFL. The stepwise linear regression analysis of SFL showed Davey score-SG se- verity as the most dominant parameter (62.2±3.3; beta:0.67, P = 0.0001, adjusted R2= 0.68) affecting its linearity as seen in Table 2. BMI, ALT, weight gain, age, and creatine were the other strongest parameters effective over SFL after SG severity. In the ROC analysis, we did for the predictability of SG severity on SFL, severe SG showed a predictive potential for SFL with 95.1% specificity and 93.2% sensitivity at 791 cut- off value (area under the curve:0.987; P = 0.00001; 95% confidence interval: 0.977-0.997). BMI and delta hemoglo- bin were also analyzed for the predictability of SG severity, as seen in Figure 1. Although the delta hemoglobin did not predict the SG severity (P = 0.696), the BMI showed a po- tential for it (area under the curve:0.744; P = 0.008; 95% confidence interval: 0.689-0.798). Conclusions The present research assessed stria severity in pregnant women with CS and its relationship with the amount of SFL that occurred during CS operation. Although the dif- ference in punch weights before and after the operation was inconsistent with blood parameters indicating the bleeding status, the SG severity and the fluid loss measured during the operation showed a very strong relationship, which was a very important finding that would affect the approach of the surgeons to the patients with SG in terms of fluid loss in CS. The emergence of SG in pregnant individuals occurs as a result of pathological and histological changes as a result of mechanical tissue tension, mast cell degranulation due to elastolysis in the mid-dermis, and macrophage stimula- tion [7,17]. Gradual changes occur and collagen, elastin, and fibrillin fibers are markedly reduced. As the epidermis thins and flattens, the distance between the collagen bundles 4 Original Article | Dermatol Pract Concept. 2023;13(3):e2023175 Table 2. The stepwise linear regression analysis of surgical fluid loss (SFL). Model B SE Beta t P value Lower Upper Constant 87.4 63.13 - 1.38 0.167 -36.7 211.7 Davey Score 62.2 3.33 0.67 18.63 0.0001 55.6 68.7 BMI, kg/m2 8.5 1.84 0.16 4.59 0.0001 4.86 12.1 ALT, U/L 2.18 1.09 0.06 2.002 0.046 0.03 4.33 Weight gain, kg 4.11 1.64 0.08 2.506 0.013 0.88 7.33 Age, years 3.43 1.37 0.08 2.491 0.013 0.72 6.14 Creatine, mg/dL -8.73 4.03 -0.07 -2.16 0.031 -16.67 -0.79 ALT = Alanine aminotransferase; BMI = body mass index; SE = standard error. Dependent: The amount of SFL was defined thgrough pre/postop measurements of punches. Predictors: Age, pregnancy week, davey score, family history, BMI, weight gained during pregnancy, smoking, baby gender, baby weight, hemoglobin, pulse, diastolic/sistolic blood pressure, platelet, protrombin time, active partial tromboplastine time, INR, AST, ALT, BUN, creatinine, fibrinogen. Table 1. Demographics and clinical details of the participants. Variables None Mild Severe P value Age, years 27.4±5.3 29.3±6.1 30.0±6.0 0.566 BMI, kg/m2 26.9±3.7 29.9±4.0 32.5±4.4 0.017 Weight gain, kg 9.2±3.6 11.2±4.5 13.7±5.3 0.008 Pregnancy, week 38.4±1.1 38.4±1.5 38.3±1.2 0..874 Newborn weight, kg 3110±487.5 3161±566.2 3345±596 0.302 Newborn Gender, m/f 34 / 37 61 / 46 71 / 59 0.478 Stria History, n/m/s 37 / 31 / 3 44 / 44 / 19 13 / 42 /75 0.001 Term Status, p/e/f/l 1 / 39 / 28 / 3 6 / 54 /37 /10 3 / 76 / 44 / 7 0.401 Hb – preoperative 11.6±1.4 11.6±1.5 11.8±1.5 0.121 Hb – postoperative 10.2±1.4 10.1±1.5 10.4±1.6 0.407 Platelet count x103 238±74 246±75 240±76 0.714 PT, sec 9.7±1.47 9.72±1.5 9.78±1.78 0.847 aPTT, sec 27.7±4.4 28.2±4 27.3±4 0.622 AST, U/L 17.8±6.9 19.2±11.5 18.7±5.4 0.609 ALT, U/L 9.15±4.96 11.2±9.86 11.9±6.71 0.297 BUN, mg/dL 10.1±9.2 8.8±5 8.9±5.3 0.438 Creatinine, mg/dL 0.5±0.15 0.5±0.12 0.49±0.14 0.899 Fibrinogen, g/L 390±52 401±58 415±73 0.856 ALT = alanine aminotransferase; aPTT = activated partial thromboplastin time AST = aspartate aminotransferase; BUN = blood urea nitrogen; Hb = hemoglobin; N/M/S = None/Moderate/Severe; P/E/F/L = Pre/Early/Full/Late Term; PLT = platelet; PT = prothrombin Time. increases with the dilatation of the blood vessels, and the elastic fibers are separated [2]. As collagen and elastin are the two major components of the arterial wall, they are passive mechanical components of soft tissues and their molecular structures regulate the characteristic response of tissues to mechanical effects [20]. Previous studies reported that women with SG have problems such as adhesion and prolapsus [21,22]. However, the effects of these problems on the vessel wall in these individuals were not investigated. Surgeons should take into consideration this issue in surgical approaches such as SC where SFL is in higher amounts. Physiologically, the formation of the vascular tube occurs in a polymerized 3d collagen lattice. However, the organi- zation of vascular endothelial cells into capillary-like struc- tures does not occur on a hard surface, even if the surface is covered with a suitable matrix component [23,24]. The study by Wang et al, investigating changes in collagen fibrils, reported increased prominence of dermal blood vessels in the early period of SG [20]. This alteration, branching, and widening of vessels, involving increased numbers, promote clinical erythema and explains how the appearance of striae can be improved [25]. According to them, type-I collagen Original Article | Dermatol Pract Concept. 2023;13(3):e2023175 5 loss in individuals with SG in CS operations. As the most important point, the relationship between these losses and the severity of SG was independent of bleeding. Although it is novel research in its field, it had strengths and limitations. First, the main strength is that it is the first research to analyze the association between the severity of SG and SFL in pregnant, with a large sample size. Second, demographics such as the age, BMI, and fetal weight of all pregnant were similar which may lessen the bias when com- paring the SG groups. Because we performed the current analysis as a prospective design, we were able to compare blood data such as Hb concentration, Platelets, and RBC before and immediately after the CS to understand SFL con- tent. However, the study proceeded without any long-term follow-up. Among the participants, a collagen measurement could be made in neither the blood nor the SFL. Severe SG according to Davey score was positively asso- ciated with the SFL and evaluation of SG status is a quick method that may be used for the prediction of SFL. The severity of SG and the SFL measured during the operation showed a very strong relationship, which was a very import- ant finding that would affect the approach of the surgeons to the patients with SG in terms of fluid loss in CS. Neverthe- less, multicenter studies with more participants are needed in clinical and surgical applications to follow the classification of SG severity and thus predict the possible amount of SFL. Reference 1. 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