Study of a preoperative scoring system to predict difficult laparoscopic cholecystectomy

Introduction: Laparoscopic Cholecystectomy (LC), one of the most commonly performed surgical procedures worldwide, is accepted as the gold standard in the treatment of symptomatic gallstones. Generally laparoscopic cholecystectomy has low incidence of morbidity, mortality and conversion rate to open surgery, but occasionally surgeons encountered diffi culty while doing Laparoscopic cholecystectomy. Preoperative prediction of “diffi cult Laparoscopic cholecystectomy” improve the patient safety as well as useful in reducing the cost of therapy. Aim: To study a scoring system based on various risk factors to preoperatively predict diffi cult Laparoscopic cholecystectomy. Materials & method: This study was conducted in Department of General surgery, Nalanda Medical College And Hospital Patna & associated All India Institute of Medical Science Patna. A total of 105 patients were included in this study. There are total 15 score from history, clinical & sonological fi ndings. They were evaluated & scored on the basis of scoring system. Score upto 5 is defi ned as easy, 6-10 as diffi cult and 11-15 as very diffi cult. Result: Prediction comes true in 96.6% for easy, 87.8% for diffi cult & 60% for very diffi cult cases. Area under ROC curve is 0.96 and conversion rate is 3.8 in our study. Age >50 years, Male sex, H/o of hospitalisation due to acute cholecystitis, Palpable gallbladder, BMI >27.5, Abdominal scar, Thick walled GB (>4mm), and Pericholecystic collection were found to be signifi cant predictive factors for diffi cult laparoscopic cholecystectomy. Conclusion: With the help of preoperative prediction, high risk patients may be informed & counseled before about probability of open conversion & diffi culty in laparoscopic cholecystectomy.


Introduction
Laparoscopic Cholecystectomy (LC), one of the most commonly performed surgical procedures worldwide, is accepted as the gold standard in the treatment of symptomatic gallstones [1]. Generally laparoscopic cholecystectomy has low incidence of morbidity, mortality and conversion rate to open surgery, but occasionally surgeons encountered diffi culty while doing Laparoscopic cholecystectomy [2]. This scoring system was developed by Randhawa & Pujahari [4].

Aims and objectives
The aim of this study was to fi nd out the validity of preoperative scoring system developed by Randhawa, et al. [4] to predict diffi cult laparoscopic cholecystectomy and chances of conversion from laparoscopic to open cholecystectomy.  (Table 1). All surgeries were done by classical four port method by using CO 2 pneumoperitoneum with 10mmHg pressure. Time were noted from fi rst port insertion till last port closure. All intraoperative events were noted like adhesions at calot's triangle, duration of surgery, injury to artery/duct, bile/stone spillage etc. (Table 2).

Statistical methods
The collected data was compiled in a Microsoft Excel sheet, and subsequently suitable multivariate logistic regression analysis using SPSS 16   Increasing age is associated with an increased probability of multiple attacks of cholecystitis and also increased frequency of upper abdominal surgeries. Therefore, there is increased incidence of fi brosis and adhesions in the hepatic hilum.
Randhawa, et al. [4] found that age more than 50 years is associated with the same diffi culties. In many studies, it was also found as a signifi cant risk factor for diffi cult LC [9,10]. So it is observed that our fi nding is consistent with other studies [4,7,11]. Out of 105 patients, 14 were male and 91 were female.
Diffi culty in Male sex surgery reported in various studies [10,15,16]. Also high Conversion rate and signifi cantly higher mortality has been reported in male patients [17]. In our study also it has been found as a signifi cant factor (P < 0.000).
There is a direct correlation between previous history of hospitalization due to acute attacks of cholecystitis and the diffi culty level of laparoscopic cholecystectomy. Each attack  Pericholecystic collection was found to be a signifi cant factor in our study (P < 0.001) concurrence with the study of Agrawal, et al. [11] In some studies it was not found as a signifi cant predictive factor like Randhawa, et al. [4]. Gupta N, et al. [7].
Diffi cult dissection secondary to dense adhesions at calot's triangle was the most common cause for diffi cult laparoscopic cholecystectomy in this study. The other causes were contracted GB with dense adhesion, distended GB with omental adhesion, short & dilated cystic duct leading to inability to apply clips, distended Hartmann's pouch, CBD injury, bleeding from gallbladder bed and tear of cystic artery, tear of gallbladder with spillage of stones and bile.  [7] on this scoring method had sensitivity and specifi city of 95.7% and 73.7% respectively with positive predictive values for easy and diffi cult as 90% and88%, and area under ROC curve as 0.86 [7]. Another study done by Randhawa, et al. [4] had sensitivity and specifi city of 75.00% and 90.24%, respectively. Prediction came true in 88.8% for easy and 92% diffi cult cases and ROC curve was 0.82. So, in our study this preoperative scoring system was found to be more sensitive & specifi c than previous studies. But positive predictive value for diffi cult cases was less as compared to the fi ndings published by Randhawa, et al. [4] & Gupta N, et al. [7]. This may be due to small sample size of our study as compared to Randhawa, et

Conclusion
From this study, we can conclude that preoperative scoring system is a good, reliable and useful method to predict diffi culty in laparoscopic cholecystectomy in majority of cases and should be used as a screening procedure. It can help surgeons to get an idea of the potential diffi culty to be faced in a particular patient. It can help in operative planning and the high risk patients may be informed accordingly.