Efficacy of Preoperative Imaging Features and Blood Tests in Predicting the Increased Risk of Conversion in Laparoscopic Appendectomy Surgery

Abstract

Background In this study, we identified preoperative risk factors, including imaging features and blood tests, to predict conversion from laparoscopic appendectomy to open appendectomy. Thus, we aimed to prevent patients from being exposed to the risks of laparoscopy by choosing patients for whom proceeding directly to an open surgery as an initial approach was appropriate. Patients and methods The cohort of 632 patients who underwent laparoscopic appendectomy due to acute appendicitis in our center between January 2017 and March 2021 were analyzed, and 521 of these patients comprised the study population. Baseline characteristics, medical history, preoperative laboratory tests, imaging features, and postoperative pathologic findings of all patients according to groups who underwent laparoscopic appendectomy or conversion to open appendectomy were examined. Results Among 521 patients, the appendectomy procedure was completed laparoscopically in 498 (95.6%) patients, and conversion to open appendectomy was occurred in 23 (4.4%) patients. 223 (42.8%) patients were female, and 298 (57.2%) patients were male. The mean age of all patients was 35.17±12.61 years (range, 16-80 years). Preoperative ultrasonography feature associated with a higher rate of conversion was free fluid collection (p=0.001). The levels of C-reactive protein, neutrophil, and neutrophil/lymphocyte ratio on admission were found to be significantly higher in the conversion group compared to the laparoscopy group (p=0.001, p=0.027, p=0.02, respectively). Conclusions Free fluid collection detected by ultrasonography, and elevation of C-reactive protein, neutrophil, and neutrophil/lymphocyte ratio may be useful in the prediction of a high risk of conversion appendectomy. Despite the unquestionable advantages of laparoscopic surgery, there are still substantial conversion rates. Within this framework, our study will help the surgeons to choose the most appropriate surgical methods for patients by evaluating them individually, and to inform them of the possibility of conversion to the open approach, and other risks before surgery.

Risk Factors for Conversion from Laparoscopic to Open Appendectomy

“…These intraoperative parameters have also already been reported in the literature [14,17]. The association of a higher preoperative WBC count with an increased conversion rate, which was detected in our study, has not been described in previous studies [12,15,16,21]. Similarly to an increased CRP, an increased WBC count may also represent the expression of a more advanced appendicitis, which makes this association appear plausible.…”

“…The identification of five of the six aforementioned risk factors is supported by previous studies [8,14,16,17,21]. Aydin et al and Yigit et al already demonstrated a significantly higher preoperative CRP level in patients who required conversion compared to those undergoing laparoscopic appendectomy, although the optimal cut off for a high CRP level varies slightly between the studies (≥108.5 mg/dL [12] and ≥119 mg/dL [15] vs. ≥95 mg/dL in our study). The level of the preoperative CRP may express the extent of appendicitis, which may be decisive for the decision to convert.…”

“…Finnerty et al reported a higher incidence of wound infection after conversion when compared with open and laparoscopic approaches [ 8 ]. Moreover, the literature confirms a higher rate of re-surgery and readmissions and a prolongated postoperative stay in patients requiring conversion [ 8 , 13 , 14 , 15 ]. In addition, although it was not investigated in our study, there are data from an American study that could reveal significantly higher costs in the group of converted patients compared the open or laparoscopic approaches [ 8 ].…”

“…Therefore, preoperative factors associated with a high risk of conversion becoming necessary might help in the decision regarding the optimal surgical approach for patients with acute appendicitis. Previous studies were already able to identify different parameters, including age, gender, diabetes, ASA Score, WBC and CRP values, the results of preoperative CT-scan, and the intraoperative presence of complicated appendicitis [ 8 , 12 , 13 , 14 , 15 , 16 , 17 ]. For example, Abe et al were able to identify CT inflammation grade 4 or 5, complicated appendicitis, higher preoperative CRP level, and diffuse peritonitis as risk factors for conversion [ 14 ]; Gupta et al showed that the conversion rate is highest in male patients above 45 years of age, with over 5 days’ duration of symptoms, leukocytosis of >20,000, and ruptured appendicitis on computed tomography scan [ 16 ]; and in the study of Antonacci et al, only the presence of comorbidities was independently associated with conversion [ 17 ].…”

The use of C‐reactive protein to predict uncomplicated appendicitis and increase uptake of laparoscopy in low resource hospitals—A retrospective cohort study

“…There is a close correlation between the presence of complicated appendicitis and the need to convert to an open procedure. 16,17 The correlation between elevated CRP and the severity of acute appendicitis has been examined in previous studies. The results found in these adult populations have been variable.…”