Laparoscopic cholecystectomy for gallbladder stone disease: preoperative factors associated with difficult operations

Laparoscopic cholecystectomy become the treatment of choice for symptomatic gallstone disease. Difficult procedure may confront the surgeon, but these situations are often predictable based on a number of clinical and paraclinical factors. This study aimed to determine which clinical and paraclinical factors are associated with difficult laparoscopic cholecystectomy. Total of 405 patients with symptomatic gallstone disease, who underwent laparoscopic cholecystectomy between 1 Marc 2018 and 29 February 2020,in 22 May Hospital, Aden, were included in the study. Patient with gallbladder cancer or acalcular cholecystitis were excluded from the study. Relevant data which include clinical and paraclinical findings as well as operative findings were collected to a specially designed questionnaire form. Data analysis was done by SPSS version 17 software. Univariate analysis for categorical variables was done using Chi square or Fischer's exact test. Continuous data were tested for normal distribution and analyzed using Mann Whitney test. Pvalue <0.05 was considered statistically significant. Female preponderance (88.1%) was observed. Mean age was 42.6 ± 13.7. Difficult laparoscopic cholecystectomy found in 137 patients (33.8%). A statistically significant association were found between difficult laparoscopic cholecystectomy and gender (p-value <0.001), history of obstructive jaundice (p-value<0.001), previous endoscopic retrograde cholangio-pancreaticography (p-value <0.001), previous abdominal surgery (p-value =0.005), white blood cell count (p-value= 0.001), gallbladder wall thickness ≥ 4mm (p-value <0.001) , impacted stone in cystic duct (p-value <0.001), pericholecystic fluid collection (p-value <0.001), dilated common bile duct more than 7 mm (p-value =0.001), contracted gallbladder despite adequate fasting (p-value <0.001). Number of preoperative factors were identified, which have statistically significant association with difficult laparoscopic cholecystectomy. Knowledge of these factors by the surgeon before operation is imperative to make the necessary precautions before operation.


Introduction:
Laparoscopic cholecystectomy has become the treatment of choice for symptomatic cholelithiasis [17], because it has several physiological advantages over open cholecystectomy, such as less post operative pain, faster return of bowel function, shorter hospital stay. It can be carried out with reduced morbidity and mortality [1,2,6,7,8] . Indeed, it is considered to be the most common laparoscopic procedure in general surgery [12].
With increasing experience, surgeons have started to take more difficult cases which were considered contraindication for laparoscopic removal of gallbladder few years back. For example, morbid obesity and previous abdominal surgery which were absolute contraindications for laparoscopic cholecystectomy have no longer remained absolute contraindication. Attempt can be made in all cases of gallstone disease with laparoscopic procedure except for patients with bleeding diathesis or patient not fit for general anesthesia [17].
Conversion to open surgery usually indicates difficult procedure, rather than being considered as complication or failure [10]. The decision to convert should be regarded as sign of good judgment in the presence of adverse operative conditions [5,24].
The reported conversion rate from laparoscopic to open cholecystectomy varies substantially between individual surgeons, with most series reporting rate ranging from 2 to 15% [17,19,24]. It is associated with increased morbidity, prolonged hospitalization, and longer recovery. Converted cases associated with increased number of infectious and other post operative complications, increased additional procedure and high 30 days readmission rate [27].
Laparoscopic cholecystectomy is a common operation which may vary in operative difficulty. Factors leading to difficult cholecystectomy can be predicted [3,26]. Thus for a surgeon, it would be helpful to establish the factors that lead to difficult cholecystectomy preoperatively. The greater understanding of these factors and the potential post operative complications is an essential part of safe surgical practice [17].
Therefore, this study aimed to determine factors associated with difficult cholecystectomy in 22 May Hospital, Aden.

Method:
This is a hospital based observational study. Total of 405 patients with symptomatic gallstone disease who underwent laparoscopic cholecystectomy between period of 1 st March 2018 and 29 th February 2020, in 22 May Hospital, were included in the study. Patients with gallbladder cancer or acalcular cholecystitis were excluded from the study. Difficult laparoscopic cholecystectomy was defined as operative time longer than 60 minute, blood loss more than 300 ml, need for senior surgeon assistance, conversion to open or partial cholecystectomy, or injury to bile duct. Relevant data, which include clinical and paraclinical findings as well as operative findings were collected to a specially designed questionnaire by the author. Data analysis was done by SPSS vs 17 software. Univariate analysis for categorical variables was done using Chi square or Fischer's exact test, pvalue <0.05 was considered statistically significant. Continuous data were tested for normal distribution and analyzed using Mann Whitney test, p-value <0.05 was considered statistically significant.

Results:
Total of 405 patients were included in the study. They were prepared for intent to undergo laparoscopic cholecystectomy. Composed of 357 female (88.1%) and 48 males (11.9%). The mean age was 42.6 with standard deviation of 13.7, which ranged from 12 to 80 years. 75% of patients were below age of 50 and the frequency of age distribution showed positive skewness. The study population was originated from different governorates as illustrated in table 1.  10 factors out of 18 were found to have statistically significant association with difficult laparoscopic cholecystectomy namely, gender (p-value <0.001), history of obstructive jaundice (p-value<0.001), previous endoscopic retrograde cholangio-pancreaticography (p-value <0.001), previous abdominal surgery (p-value =0.005), white blood cell count (p-value= 0.001), gallbladder wall thickness ≥ 4mm (p-value <0.001), impacted stone in cystic duct (p-value <0.001), pericholecystic fluid collection, dilated common bile duct more than 7 mm (p-value= 0.001), contracted gallbladder despite adequate fasting (p-value <0.001). The last five of the above mentioned variables are abdominal ultrasound findings.

Discussion:
Laparoscopic cholecystectomy become the modality of choice for the treatment of symptomatic gallbladder disease [12,16,27]. Although difficulty during the surgery may astonish the surgeon, most of the difficult situations can be predicted preoperatively by a number of warning clinical and paraclinical findings [3,22,24,29].
In many published studies, age is recognized as a risk factor for difficult laparoscopic cholecystectomy [2,6]. However, this study did not revealed statistically significant association between age and difficult laparoscopic cholecystectomy. This is in consistency with the study by Jethwani U et al [11] and Sudhir M and Pruthvi R [25]. In their studies, age had no significant impact on prediction of difficult laparoscopic cholecystectomy.
In the current study found female preponderance (88.1%), a finding which is in consistence with several study reports [2,6,12,15,21,22,23,27,28]. High incidence of gallstones in females has been suggested due to the effect of estrogen and progesterone on biliary cholesterol level and gallbladder motility [2,6]. Interestingly, in the current study, male gender was identified as a risk factor for difficult laparoscopic cholecystectomy on univariate. Similarly, several reports in the literature have identified male gender as risk factor for difficult laparoscopic cholecystectomy [17,29]. In context of symptomatic gallbladder stones, inflammation and fibrosis are more extensive in men than women [31]. These findings help explain why the rate of conversion to open surgery is higher in male then female. By Vivek M et al, male sex was associated with difficulty in adhesiolysis and Callot's triangle dissection [30].
In the study, no statistical relation found between duration of symptoms and laparoscopic cholecystectomy. Some literature suggest that duration of symptoms is acceptable factor for prediction of difficult laparoscopic cholecystectomy [9]. An episode of biliary pain within 15 days prior to surgery was associated with longer operating time, but it did not affect the reported preoperative difficulty or the rate of conversion [13].
The present study did not identify diabetes mellitus (DM) as an independent risk factor for difficult laparoscopic cholecystectomy. Kulkarni S. and Kumar S. noticed that concomitant association of diabetes mellitus failed to show significant correlation with surgeon's difficulty or conversion rate [13]. Similarly, a meta-analytic study by Rothman J et al found no association between DM and difficult laparoscopic cholecystectomy [20].
Previous abdominal surgery is a clinical parameter, which was found to have statistical association with difficult laparoscopic cholecystectomy. Consistently, Abdulhamid M et al found significant association with it and open conversion [2]. Mudgal M et al regarded previous abdominal surgery as significant predictive factor for difficult laparoscopic cholecystectomy [15]. Leukocyte count showed statistically significant association with difficult laparoscopic cholecystectomy on univariate analysis (Man-Whitney test) with significance of p = 0.001.
Similarly, Verma D. et al found statistically significant association between leukocytosis (>11,000/ cu mm) and difficult laparoscopic cholecystectomy. However, they converted leukocyte count to categorical variable (leukocytosis or no leukocytosis) in their study [29].
Previous ERCP, a disease related factor was found a significant predictor for difficult laparoscopic cholecystectomy. Similarly, Sutcliffe R et al found in their study, ERCP to be significantly associated with conversion to open surgery on univariate analysis [27]. According to Pol M. et al, previous surgery and adhesions following post ERCP cholelithiasis, constitute the major risk factor for laparoscopic cholecystectomy converted to open surgery [18].
Preoperative ultrasound finding of thickened gallbladder wall more than 4mm, was found to be a significant predictor of difficult laparoscopic cholecystectomy. Mudgal M et al found difficult laparoscopic cholecystectomy as well as conversion to open cholecystectomy significantly high in patient with thickened gallbladder wall [15]. Kulkarni S. and Kumar S reported that contracted gallbladder and gallbladder wall thickness >4mm were strongly related to increased duration of surgery [13].
Impacted stone is another sonographic finding which found to have strong statistical association with difficult laparoscopic cholecystectomy. It was found to be a statistically significant factor in predicting difficulty of the procedure [4]. Similarly, Singh K et al concluded that ultrasound finding of impacted stone in the cystic duct is a significant predictor of difficult laparoscopic cholecystectomy. Likewise, Abdelhamid M et al found strong correlation between it as well as pericholecystic fluid collection and difficult laparoscopic cholecystectomy.