J. Lumbini. Med. Coll. Vol 8, No 1, Jan-June 2020 Bajracharya S, et al. Bajracharya S, et al. Effectiveness of Structured Teaching Program on Menstrual Hygiene among Adolescent School Girls. . Licensed under CC BY 4.0 International License which permits use, distribution and reproduction in any medium, provided the original work is properly cited. ___________________________________________________________________________________ Submitted: 1 May, 2020 Accepted: 31 May, 2020 Published: 02 June, 2020 a - Lecturer, b- Assistant Professor, c- Professor, d- Department of Surgery, Lumbini Medical College Teaching Hos- pital, Palpa, Nepal. Corresponding Author: Suman Baral e-mail: brylsuman.sur@gmail.com ORCID: https://orcid.org/0000-0003-0906-138X_______________________________________________________ –————————————————————————————————————————— ABSTRACT: Introduction: Preoperative prediction of the factors leading to difficulty or conversion in cholecystectomy could help plan the surgical strategies and possible outcomes beforehand. The present study aimed to predict and analyze risk factors using a scoring system deemed responsible for surgical difficulties in patients undergoing cholecystectomy for symptomatic cholelithiasis. Methods: This hospital based prospective study was conducted at Department of Surgery, Lumbini Medical College and Teaching Hospital, Nepal. Various factors considered preoperatively were gender, age, previous history of hospitalization, impacted stone, obesity, gall bladder wall thickness, pericholecystic collection, previous abdominal scar and palpable gall bladder. Results: Among 177 cases operated, the mean age ±SD of the patients was 47.72±17.54 years. Conversion rate was 7.9 %. At preoperative score of 5; sensitivity, specificity, positive predictive value and negative predictive value were 89.40% (CI: 83.36%-93.82%), 69.23% (CI: 48.21 %-85.67%), 94.41%(CI: 90.44%-96.79%) and 52.94% (CI: 39.85%-65.64%) respectively{Area under curve– 0.74, p=0.0001, CI (0.637-0.846)}. Multivariate analysis showed abdominal scar {p=0.02, OR (CI): 5.2 (1.2-21.8)}, previous hospitalization {p=0.001, OR(CI): 6.8(2.2-20.8)} and thickened gall bladder wall {p= 0.03, OR(CI): 3.6(1.1- 11.5)} to be statistically significant risk factors. Conclusion: With possible prediction beforehand, high risk group of patients can be identified and dealt accordingly to generate good surgical outcome avoiding complications. Key Words: Conversion, Laparoscopic cholecystectomy, Preoperative prediction Original Research Articlehttps://doi.org/10.22502/jlmc.v8i1.297 Suman Baral,a,d Neeraj Thapa,b,d Raj Kumar Chhetri c,d Validation of A Preoperative Scoring System to Predict Difficult Laparoscopic Cholecystectomy: A Nepalese Perspective How to cite this article:How to cite this article: Baral S, Thapa N, Chhetri RK. Validation of A Preoperative Scoring System to Predict Difficult Laparoscopic Cholecystectomy: A Nepalese Perspective. Journal of Lumbini Medical College. 2020;8(1):7 pages Journal of Lumbini Medical College. 2020;8(1):7 pages DOI: DOI: https://doi.org/10.22502/jlmc.v8i1.323. Epub: 2020 June 02.. Epub: 2020 June 02. INTRODUCTION: Laparoscopic Cholecystectomy(LC) is one of the most common surgical procedures performed worldwide and is the procedure of choice for the management of symptomatic gall stones.[1] Though this has been considered one of the safest surgeries to begin with laparoscopy, it requires meticulous dissection and good exposure of Calot’s triangle in order to prevent bile duct injuries.[2] Dense adhesions at Calot’s triangle and patients presenting with chronic cholecystitis with fibrotic and contracted gall bladder sometimes make surgery difficult and chances of conversion remains.[3] Various preoperative risk factors include male sex, old age, features of acute cholecystitis with fever and leukocytosis, obesity, previous surgery leading to abdominal scar, ultrasonographic findings like thickened gall bladder wall more than 4 mm, distended gall bladder, pericholecystic collection, impacted stone etc. which make laparoscopic surgery difficult.[4] Preoperative prediction of difficulty in laparoscopic surgery and grading scales have widely been studied.[3,5,6] They have an advantage for the J. Lumbini. Med. Coll. Vol 8, No 1, Jan-June 2020 Baral S, et al. Validation of A Preoperative Scoring System to Predict Difficult Laparoscopic Cholecystectomy: A Nepalese Perspective jlmc.edu.np operating surgeon regarding quantifying the high- risk cases, managing operation room schedules, and counselling the relatives before the surgery about the potential complications. Also, the surgeons can prepare themselves for the adverse outcomes like arranging logistics and facilities, seeking help from seniors and colleagues. The present study aimed to utilize a preoperative scoring system and validate its applicability in a tertiary hospital of a developing country. METHODS: This was a prospective cross-sectional study conducted in the Department of Surgery, Lumbini Medical College Teaching Hospital after the approval from Institutional Review Committee (IRC-LMC 02-E/019). The study commenced from 15th July 2019 to 14th March 2020 for a period of eight months. Proper history and physical examination were carried out along with abdominal ultrasonography (USG). Laboratory parameters like Complete Blood Count (CBC), Liver Function Test (LFT) and preoperative laboratory assessment were carried out regarding fitness for surgery. All the patients with symptomatic gall stone disease including acute calculus cholecystitis were included in the study. Those patients who were unfit for general anesthesia, acute calculus cholecystitis managed conservatively, and those with chronic liver disease, choledocholithiasis and features of obstructive jaundice were excluded. A preoperative difficulty scoring system developed by Randhawa et al. was used in the present study. [7] The patients were assigned their difficulty level according to history, clinical parameters and USG findings ( Table 1). History included variables like age, sex and past history of hospital admission for acute cholecystitis. Clinical parameters included Body Mass Index (BMI) which was designated 18.5-24.9 kg/m2 being normal weight as per WHO classification[8] and more than 25 kg/m2 was taken as risk factors which was splitted to 25-27.5 kg/m2 and more than 27.5 kg/m2 to corroborate with the scoring system, abdominal scar following previous abdominal surgery, and presence of clinically palpable gall bladder. A performa was filled up by the operating surgeons before attending surgery. The patients were admitted a day before the procedure, evaluated for the surgical fitness and posted for surgery the next day as electives which applies for acute calculus cholecystitis cases too. All the surgeries were performed by experienced surgeons. Table 1. Scoring factors used for grading the patient parameters Patient Characteristics (N= 177) Score Age (years) <50 0 ≥50 1 Sex Male 1 Female 0 History of hospitalization for acute cholecystitis Yes 4 No 0 BMI <25 0 25-27.5 1 >27.5 2 Abdominal scar Infra- umbilical 1 Supra- umbilical 2 No 0 Palpable gall bladder Yes 1 No 0 Thick gall bladder wall ≥4 mm 2 <4mm 1 Pericholecystic collection Yes 1 No 0 Impacted stone Yes 1 No 0 Score: 0-5: Easy 6-10: Difficult 11-15: Very Difficult Surgery was conducted creating CO2 pneumoperitoneum through open Hasson method. The 4-port technique was used with umbilical as camera port, epigastric as working port, and two 5mm ports on mid clavicular and anterior axillary line. Attaining a critical view of safety was the major goal, starting the dissection posteriorly and artery first clipping followed by cystic duct was the method we follow. However, Intraoperative Cholangiogram (IOC) was not done because of lack of feasibility and assets. Open conversion was done if critical view of safety was not attainable along with reconstituting subtotal cholecystectomy in cases of frozen calot’s triangle where complete removal of gall bladder was deemed impossible. Total duration of surgery was the time after the commencement of skin incision and layer by layer closure after the procedure. All intraoperative events like bile spillage, bile duct injury or open conversion were recorded. The preoperative scores were compared with the J. Lumbini. Med. Coll. Vol 8, No 1, Jan-June 2020 Baral S, et al. Validation of A Preoperative Scoring System to Predict Difficult Laparoscopic Cholecystectomy: A Nepalese Perspective jlmc.edu.np intraoperative assessment (Table 2). Table 2. Showing the parameters and scoring/ grading on the basis of intraoperative assessment. Parameters Score Grading Time taken <60 minutes and No Bile Spillage and No injury to duct 0-5 Easy Time taken 60-120 minutes and/or bile or stone spillage and/or injury to duct 6-10 Difficult Time taken > 120 minutes or conversion 11-15 Very Difficult Statistical analysis was performed with Statistical Package for Social Sciences (SPSSTM) software version 20. Chi-square test/ Fisher exact test was used to find significance of association between preoperative and intraoperative findings for categorical variables whilst student-t test was used for continuous variables. Univariate and multivariate analysis were done to predict the risk factors for difficulty in surgery using binary logistic regression on the basis of intraoperative outcome as easy or difficult. Area under the Receiver Operating Characteristic (ROC) curve was used to find the diagnostic and predictive value of preoperative score for predicting the intraoperative outcome. Similarly, sensitivity and specificity of the proposed preoperative scoring system at our setting were also determined. P value <0.05 was considered statistically significant. RESULTS: There were 190 patients with symptomatic cholelithiasis during the study period. However, 13 of them did not fulfill the inclusion criteria. One hundred and seventy-seven patients under went laparoscopic cholecystectomy which included 36 males and 141 females. The mean age±SD of the patient was 47.72 ± 17.54 years. Twenty-four patients had past history of hospitalization for acute calculus cholecystitis while 12 had prior history of surgery with abdominal scar mostly midline. Gall bladder was palpable clinically in 27 patients. Seventeen patients had thickened gall bladder wall more than 4 mm. Pericholecystic collection was seen in 15 patients while impacted stone was observed in 16 cases. Fourteen patients needed conversion to open cholecystectomy with conversion rate of 7.9% (Table 3). Conversion occurred due to difficulty in dissection owing to dense adhesions rather than biliary spillage or uncontrolled intraoperative bleeding. Mean operative time was 51.16 ± 15.27 minutes for easy cases and 62.79 ± 16.66 minutes for difficult cases. Table 3: Distribution of Parameters. Patient Characteristics (N= 177) Frequency Age (years) <50 96 >50 81 Sex Male 36 Female 141 History of hospitalization for acute cholecystitis Yes 24 No 153 BMI <25 108 25-27.5 42 >27.5 27 Abdominal scar Yes 12 No 165 Palpable gall bladder Yes 27 No 150 Thick gall bladder wall Yes 17 No 160 Pericholecystic collection Yes 15 No 162 Impacted stone Yes 16 No 161 Conversion 14 Table 4: Preoperative Score and the outcome Pre- operative Score Easy Difficult Very Difficult Total 0-5 135 14 2 151 6-10 8 6 12 26 11-15 - - - - Total 143 20 14 177 Most of the patients had preoperative score of 0-5 and most were easy. None of the patients had score above 10 pre-operatively (Table 4). However, 14 patients were labelled very difficult according to intraoperative assessment. Considering preoperative score of 5; sensitivity, specificity, J. Lumbini. Med. Coll. Vol 8, No 1, Jan-June 2020 Baral S, et al. Validation of A Preoperative Scoring System to Predict Difficult Laparoscopic Cholecystectomy: A Nepalese Perspective jlmc.edu.np Positive PredictiveValue (PPV) and Negative Predictive Value (NPV) were 89.40% (CI: 83.36%- 93.82%), 69.23%(CI: 48.21 %-85.67%), 94.41%(CI: 90.44%-96.79%) and 52.94% (CI: 39.85%-65.64%) respectively.Area under the Receiver Operating Characteristic (ROC) curve was 0.74{p value – 0.0001, CI: (0.637-0.846} (Figure 1). Univariate analysis of intraoperative outcome with risk factors showed abdominal scar due to previous surgery, previous hospitalization for acute calculus cholecystitis managed conservatively during previous episode, thickened gall bladder wall more than 4 mm and impacted gall bladder stone to be statistically significant ( p value <0.05). Multivariate analysis depicted abdominal scar {p=0.02, OR(CI) 5.2 ( 1.2-21.8)}, previous hospitalization {p=0.001, OR(CI):6.8(2.2-20.8)} and thickened gall bladder wall {p= 0.03, OR(CI):3.6(1.1-11.5)} to be statistically significant risk factors (Table 5). Fig. 1. Receiver Operating Characteristic (ROC) curve and Area Under the Curve (AUC) for prediction of intra-operative outcome based on preoperative scores. Table 5: Predictive association of risk factors with intraoperative outcome Risk Factors Level Intra-Operative Outcome Univariate (OR-CI) Multivariate (OR-CI) Easy Difficult Age <50 70 14 ≥50 59 20 p=0.177 OR=1.7(0.78-3.6) Sex Female 108 24 Male 21 10 p=0.08 OR=2.1(0.89-5.1) BMI <25 92 19 25-27.5 25 11 p=0.08 OR=2.1(0.89-5.0) >27.5 12 4 p=0.44 OR=1.6(0.47-5.5) Abdominal Scar No 124 29 Yes 5 5 p=0.02 OR=4.2 (1.1-15.7) p=0.02 OR= 5.2 (1.2- 21.8) Previous hospitalization for acute calculus cholecystitis No 121 22 Yes 8 12 p=0.0001 OR=8.2 (3.0-22.5) p=0.001 OR= 6.8 (2.2- 20.8) Palpable gall bladder No 116 27 Yes 13 7 p= 0.104 OR=2.3 (0.84-6.3) Thick Wall ≥ 4mm No 120 26 Yes 9 8 p=0.008 OR= 4.1 (1.4-11.6) p=0.03 OR= 3.6 (1.1- 11.5) Pericholecystic Collection No 119 32 Yes 10 2 p=0.711 OR= 10.7(0.15-3.5) Impacted Stone No 124 26 Yes 5 8 p=0.001 OR=7.6 (2.3-25.2) J. Lumbini. Med. Coll. Vol 8, No 1, Jan-June 2020 Baral S, et al. Validation of A Preoperative Scoring System to Predict Difficult Laparoscopic Cholecystectomy: A Nepalese Perspective jlmc.edu.np DISCUSSION: Laparoscopic Cholecystectomy (LC) is one of the most commonly performed surgeries worldwide and has been considered gold standard for the treatment of symptomatic gall stones. Because of the propensity of lesser post-operative pain, cosmesis, shorter hospital stay and disability from work, this has been the choice of procedure for maximum patients worldwide.[9,10] However, post-operative complication rates have been found higher in minimal invasive procedures like LC in comparison to open surgeries.[11] Safe laparoscopic surgery has become one of the most important topics discussed and various studies are ongoing regarding well-being of the patient and surgeon himself. Intraoperative findings may not be similar in every case and these greatly vary upon clinical presentation and surgical challenges might arise for the operating surgeon. If the prediction of safety of surgery could be made beforehand, surgeon will have a range of benefits like planning for surgery, patient counselling, operating room preparation and scheduling, and prepare for help from seniors and colleagues if needed.[12] Increasing age or elderly population tend to be an important risk factor for difficulty in surgery as they are likely to have more longstanding disease with higher likelihood of complicated biliary tract disease which gets superimposed by various co- morbidities.[13] Various studies have concluded that older age is one of the significant risk factors.[7, 14] However, our study could not corroborate with their findings which other studies did too (p=0.177). [3,15] This could be due to cut off of age group as more than 50 years as some studies predicted using the cut off of 40 years.[12] The role of gender has also been mentioned in literatures as male population showed trends of high risk of conversion and surgical difficulty.[7,12,16,17] However, in our study, gender was not related to high risk of conversion. There was not any significant association between gender as male patients showing difficult surgeries or conversion rates (p= 0.08) which was also seen in study by Gupta et al.[3] This could be due to less sample population of males who were operated in comparison to female groups. Previous history of hospitalization for acute cholecystitis managed conservatively is one of the risk factors for difficulty in surgery which has been clarified by our study too (p=0.001, OR=6.8). This can be explained as the chances of difficulty that may lead to conversion are about six times higher than those groups of people who have not been previously admitted or treated conservatively for acute cholecystitis. The absence of previous repeated attacks of cholecystitis and hospitalizations has been clarified to determine safe surgery in a study from Montenegro.[18] Pathogenesis could be repeated scarring and fibrosis of gall bladder due to multiple colic. Obesity or high BMI also has been considered the risk factor for conversion in another study.[19] However, this was not statistically significant in our study. Abdominal scar due to previous surgery may develop adhesions of viscera to the anterior abdominal wall and chances of conversion remains as risk of injury to bowel or other visceral structures are prudent during insertion of trocars.[20] Our study concluded the same ( p= 0.02, OR = 5.2). This suggests the chances of difficulty are five times in patients with past history of surgery leading to abdominal scar. Thickened gall bladder wall more than 4 mm is one of the sonological criteria for diagnosis of acute cholecystitis and this has been attributed to difficulty in surgery or chances of conversion in various studies. [21,22] Palpable gall bladder due to development of mucocele or cholecystitis leading to empyema could render surgery difficult due to inability to grasp the fundus of the gall bladder leading to perforation and spillage of bile or pus along with gall stones in the peritoneal cavity. A study by Randhawa et al.[7] has correlated the significant association of palpable gall bladder with intraoperative difficulty which is also supported by Gupta et al.[3] Pericholecystic collection was seen in 12 patients in our study. However, no significant association was seen with difficulty in laparoscopy (p= 0.71) which was consistent with that observed in studies from Delhi and Banglore, India.[3,7] Impacted stone was significantly associated with difficulty in laparoscopic cholecystectomy which has been concluded in other studies too.[3,5] Preoperative difficulty scores seem not coordinating with intraoperative scoring at score level of 6-10 in difficult surgeries. Difficult numbers are small however we could see increased very difficult cases that corroborates the preoperative level of difficulty. This could be due to selection bias; a smaller number of sample size and the intraoperative scoring system could be merged as very difficult level to difficult considering only two intraoperative variables modifying the scoring system. Also, none of the samples attained very difficult score J. Lumbini. Med. Coll. Vol 8, No 1, Jan-June 2020 Baral S, et al. Validation of A Preoperative Scoring System to Predict Difficult Laparoscopic Cholecystectomy: A Nepalese Perspective jlmc.edu.np preoperatively which could be removed. Our study could conclude sensitivity of around 90% and specificity of around 70% which can be correlated with findings from Gupta et al. who mentioned sensitivity of 95% and specificity of around 74% in his validation study.[3]Similarly, conversion rate in our case was 7.9% which is comparable to a national conversion rate in United states which was 5-10% in a nationwide study conducted on 2004 collecting sample operated from 1998 to 2001.[23]Ghnnam et al. showed the conversion of 5% at Khamis General Hospital, Saudi Arabia where he analyzed retrospectively 340 patients.[24] However, males constituted about 20%( N=36) of total operated cases and conversion rate was as high as 25 % which could be due to less sample size . Females had conversion of 3.5% in our study. CONCLUSION: The scoring system can be used clinically to predict and guide the surgeons regarding safe surgical practice and anticipate the outcomes beforehand. However, larger sample sizes and multi center studies may be required in order to validate statistically and purposeful wide spread applicability in daily schedules. Conflict of interest: Authors declare that no competing interest exists. Funding: No funds were available for the study. REFERENCES: 1. Acar T, Kamer E, Acar N, Atahan K, Bağ H, Hacıyanlı M, et al. Laparoscopic cholecystecto- my in the treatment of acute cholecystitis: com- parison of results between early and late chole- cystectomy. Pan Afr Med J. 2017;26:49.PMID: 28451027DOI: 10.11604/pamj.2017.26.49.8359 2. Suliman E, Palade RȘ, Suliman E. Importance of cystic pedicle dissection in laparoscopic cho- lecystectomy in order to avoid the common bile duct injuries. J Med Life. 2016;9(1):44-48. PMID: 27974912 3. 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PMID: 26425061 DOI: 10.4103/1117-6806.162573 22. Hu ASY, Menon R, Gunnarsson R, de Costa A. Risk factors for conversion of laparoscopic cholecystectomy to open surgery - A system- atic literature review of 30 studies. Am J Surg. 2017;214(5):920-930. PMID: 28739121 DOI: 10.1016/j.amjsurg.2017.07.029 23. Livingston EH, Rege RV.A nationwide study of conversion from laparoscopic to open cholecys- tectomy. Am J Surg. 2004;188(3):205-211. 24. Ghnnam W, Malek J, Shebl E, Elbeshry T, Ibra- him A. Rate of conversion and complications of laparoscopic cholecystectomy in a tertiary care center in Saudi Arabia. Ann Saudi Med. 2010;30(2):145-148. PMID: 20220265 DOI: 10.4103/0256-4947.60521