The development and validation of a scoring tool to predict the operative duration of elective laparoscopic cholecystectomy
Authors: Bharamgoudar Reshma , Sonsale Aniket , Hodson James , Griffiths Ewen ,   on behalf of the CholeS Study Group, West Midlands Research Collaborative, Vohra Ravinder S. , Kirkham Amanda J. , Pasquali Sandro , Marriott Paul , Johnstone Marianne , Spreadborough Philip , Alderson Derek , Griffiths Ewen A. , Fenwick Stephen , Elmasry Mohamed , Nunes Quentin M. , Kennedy David , Khan Raja Basit , Khan Muhammad A. S. , Magee Conor J. , Jones Steven M. , Mason Denise , Parappally Ciny P. , Mathur Pawan , Saunders Michael , Jamel Sara , Haque Samer Ul , Zafar Sara , Shiwani Muhammad Hanif , Samuel Nehemiah , Dar Farooq , Jackson Andrew , Lovett Bryony , Dindyal Shiva , Winter Hannah , Fletcher Ted , Rahman Saquib , Wheatley Kevin , Nieto Tom , Ayaani Soofiyah , Youssef Haney , Nijjar Rajwinder S. , Watkin Helen , Naumann David , Emesih Sophie , Sarmah Piyush B. , Lee Kathryn , Joji Nikita , Lambert Joel , Heath Jonathan , Teasdale Rebecca L. , Weerasinghe Chamindri , Needham Paul J. , Welbourn Hannah , Forster Luke , Finch David , Blazeby Jane M. , Robb William , McNair Angus G. K. , Hrycaiczuk Alex , Charalabopoulos Alexandros , Kadirkamanathan Sritharan , Tang Cheuk-Bong , Jayanthi Naga V. G. , Noor Nigel , Dobbins Brian , Cockbain Andrew J. , Nilsen-Nunn April , de Siqueira Jonathan , Pellen Mike , Cowley Jonathan B. , Ho Wei-Min , Miu Victor , White Timothy J. , Hodgkins Kathryn A. , Kinghorn Alison , Tutton Matthew G. , Al-Abed Yahya A. , Menzies Donald , Ahmad Anwar , Reed Joanna , Khan Shabuddin , Monk David , Vitone Louis J. , Murtaza Ghulam , Joel Abraham , Brennan Stephen , Shier David , Zhang Catherine , Yoganathan Thusidaran , Robinson Steven J. , McCallum Iain J. D. , Jones Michael J. , Elsayed Mohammed , Tuck Liz , Wayman John , Carney Kate , Aroori Somaiah , Hosie Kenneth B. , Kimble Adam , Bunting David M. , Hosie Kenneth B. , Fawole Adeshina S. , Basheer Mohammed , Dave Rajiv V. , Sarveswaran Janahan , Jones Elinor , Kendal Chris , Tilston Michael P. , Gough Martin , Wallace Tom , Singh Shailendra , Mockford Justine Downing Katherine A. , Issa Eyad , Shah Nayab , Chauhan Neal , Wilson Timothy R. , Forouzanfar Amir , Wild Jonathan R. L. , Nofal Emma , Bunnell Catherine , Madbak Khaliel , Rao Sudhindra T. V. , Devoto Laurence , Siddiqi Najaf , Khawaja Zechan , Hewes James C. , Gould Laura , Chambers Alice , Rodriguez Daniel Urriza , Sen Gourab , Robinson Stuart , Carney Kate , Bartlett Francis , Rae David M. , Stevenson Thomas E. J. , Sarvananthan Kas , Dwerryhouse Simon J. , Higgs Simon M. , Old Oliver J. , Hardy Thomas J. , Shah Reena , Hornby Steve T. , Keogh Ken , Frank Lucinda , Al-Akash Musallam , Upchurch Emma A. , Frame Richard J. , Hughes Michael , Jelley Clare , Weaver Simon , Roy Sudipta , Sillo Toritseju O. , Galanopoulos Giorgios , Cuming Tamzin , Cunha Pedro , Tayeh Salim , Kaptanis Sarantos , Heshaishi Mohamed , Eisawi Abdalla , Abayomi Michael , Ngu Wee Sing , Fleming Katie , Bajwa Dalvir S. , Chitre Vivek , Aryal Kamal , Ferris Paul , Silva Michael , Lammy Simon , Mohamed Sarah , Khawaja Amir , Hussain Adnan , Ghazanfar Mudassar A. , Bellini Maria Irene , Ebdewi Hamdi , Elshaer Mohamed , Gravante Gianpiero , Drake Benjamin , Ogedegbe Arikoge , Mukherjee Dipankar , Arhi Chanpreet , Giwa Lola , Iqbal Nusrat , Watson Nicholas F. , Aggarwal Smeer Kumar , Orchard Philippa , Villatoro Eduardo , Willson Peter D. , Mok Kam Wa Jessica , Woodman Thomas , Deguara Jean , Garcea Giuseppe , Babu Benoy I. , Dennison A. R. , Malde Deep , Lloyd David , Satheesan Steve , Al-Taan Omer , Boddy Alexander , Slavin John P. , Jones Robert P. , Ballance Laura , Gerakopoulos Stratos , Jambulingam Periyathambi , Mansour Sami , Sakai Naomi , Acharya Vikas , Sadat Mohammed M. , Karim Lawen , Larkin David , Amin Khalid , Khan Amarah , Law Jennifer , Jamdar Saurabh , Smith Stella R. , Sampat Keerthika , O’shea Kathryn M. , Manu Mangta , Asprou Fotini M. , Malik Nabeela S. , Chang Jessica , Johnstone Marianne , Lewis Michael , Roberts Geoffrey P. , Karavadra Babu , Photi Evangelos , Hewes James , Gould Laura , Chambers Alice , Rodriguez Dan , O’Reilly Derek A. , Rate Anthony J. , Sekhar Hema , Henderson Lucy T. , Starmer Benjamin Z. , Coe Peter O. , Tolofari Sotonye , Barrie Jenifer , Bashir Gareth , Sloane Jake , Madanipour Suroosh , Halkias Constantine , Trevatt Alexander E. J. , Borowski David W. , Hornsby Jane , Courtney Michael J. , Virupaksha Suvi , Seymour Keith , Robinson Sarah , Hawkins Helen , Bawa Sadiq , Gallagher Paul V. , Reid Alistair , Wood Peter , Finch J. G. , Guy Finch J. , Parmar J. , Stirland E. , Gardner-Thorpe James , Al-Muhktar Ahmed , Peterson Mark , Majeed Ali , Bajwa Farrukh M. , Martin Jack , Choy Alfred , Tsang Andrew , Pore Naresh , Andrew David R. , Al-Khyatt Waleed , Taylor Christopher , Bhandari Santosh , Chambers Adam , Subramanium Dhivya , Toh Simon K. C. , Carter Nicholas C. , Tate Sophie , Pearce Belinda , Wainwright Denise , Mercer Stuart J. , Knight Benjamin , Vijay Vardhini , Alagaratnam Swethan , Sinha Sidhartha , Khan Shahab , El-Hasani Shamsi S. , Hussain Abdulzahra A. , Bhattacharya Vish , Kansal Nisheeth , Fasih Tani , Jackson Claire , Siddiqui Midhat N. , Chishti Imran A. , Fordham Imogen J. , Siddiqui Zohaib , Bausbacher Harald , Geogloma Ileana , Gurung Kabita , Tsavellas George , Basynat Pradeep , Shrestha Ashish Kiran , Basu Sanjoy , Chhabra Alok , Harilingam Mohan , Rabie Mohamed , Akhtar Mansoor , Kumar Pradeep , Jafferbhoy Sadaf F. , Hussain Najam , Raza Soulat , Haque Manzarul , Alam Imran , Aseem Rabiya , Patel Shakira , Asad Mehek , Booth Michael I. , Ball William R. , Wood Christopher P. J. , Pinho-Gomes Ana C. , Kausar Ambareen , Obeidallah Moh’d Rami , Varghase Joseph , Lodhia Joshil , Bradley Donal , Rengifo Carla , Lindsay David , Gopalswamy Sivakumar , Finlay Ian , Wardle Stacy , Bullen Naomi , Iftikhar Syed Yusuf , Awan Altaf , Ahmed Javed , Leeder Paul , Fusai Guiseppe , Bond-Smith Giles , Psica Alicja , Puri Yogesh , Hou David , Noble Fergus , Szentpali Karoly , Broadhurst Jack , Date Ravindra , Hossack Martin R. , Goh Yan Li , Turner Paul , Shetty Vinutha , Riera Manel , Macano Christina A. W. , Sukha Anisha , Preston Shaun R. , Hoban Jennifer R. , Puntis Daniel J. , Williams Sophie V. , Krysztopik Richard , Kynaston James , Batt Jeremy , Doe Matthew , Goscimski Andrzej , Jones Gareth H. , Smith Stella R. , Hall Claire , Carty Nick , Ahmed Jamil , Panteleimonitis Sofoklis , Gunasekera Rohan T. , Sheel Andrea R. G. , Lennon Hannah , Hindley Caroline , Reddy Marcus , Kenny Ross , Elkheir Natalie , McGlone Emma R. , Rajaganeshan Rajasundaram , Hancorn Kate , Hargreaves Anita , Prasad Raj , Longbotham David A. , Vijayanand Dhakshinamoorthy , Wijetunga Imeshi , Ziprin Paul , Nicolay Christopher R. , Yeldham Geoffrey , Read Edward , Gossage James A. , Rolph Rachel C. , Ebied Husam , Phull Manraj , Khan Mohammad A. , Popplewell Matthew , Kyriakidis Dimitrios , Hussain Anwar , Henley Natasha , Packer Jessica R. , Derbyshire Laura , Porter Jonathan , Appleton Shaun , Farouk Marwan , Basra Melvinder , Jennings Neil A. , Ali Shahda , Kanakala Venkatesh , Ali Haythem , Lane Risha , Dickson-Lowe Richard , Zarsadias Prizzi , Mirza Darius , Puig Sonia , Al Amari Khalid , Vijayan Deepak , Sutcliffe Robert , Marudanayagam Ravi , Hamady Zayed , Prasad Abheesh R. , Patel Abhilasha , Durkin Damien , Kaur Parminder , Bowen Laura , Byrne James P. , Pearson Katherine L. , Delisle Theo G. , Davies James , Tomlinson Mark A. , Johnpulle Michelle A. , Slawinski Corinna , Macdonald Andrew , Nicholson James , Newton Katy , Mbuvi James , Farooq Ansar , Mothe Bhavani Sidhartha , Zafrani Zakhi , Brett Daniel , Francombe James , Spreadborough Philip , Barnes James , Cheung Melanie , Al-Bahrani Ahmed Z. , Preziosi Giuseppe , Urbonas Tomas , Alberts Justin , Mallik Mekhlola , Patel Krashna , Segaran Ashvina , Doulias Triantafyllos , Sufi Pratik A. , Yao Caroline , Pollock Sarah , Manzelli Antonio , Wajed Saj , Kourkulos Michail , Pezzuto Roberto , Wadley Martin , Hamilton Emma , Jaunoo Shameen , Padwick Robert , Sayegh Mazin , Newton Richard C. , Hebbar Madhusoodhana , Farag Sameh F. , Spearman John , Hamdan Mohammed F. , D’Costa Conrad , Blane Christine , Giles Mathew , Peter Mark B. , Hirst Natalie A. , Hossain Tanvir , Pannu Arslan , El-Dhuwaib Yesar , Morrison Tamsin E. M. , Taylor Greg W. , Thompson Ronald L. E. , McCune Ken , Loughlin Paula , Lawther Roger , Byrnes Colman K. , Simpson Duncan J. , Mawhinney Abi , Warren Conor , McKay Damian , McIlmunn Colin , Martin Serena , MacArtney Matthew , Diamond Tom , Davey Phil , Jones Claire , Clements Joshua M. , Digney Ruairi , Chan Wei Ming , McCain Stephen , Gull Sadaf , Janeczko Adam , Dorrian Emmet , Harris Andrew , Dawson Suzanne , Johnston Dorothy , McAree Barry , Ghareeb Essam , Thomas George , Connelly Martin , McKenzie Stephen , Cieplucha Krzysztos , Spence Gary , Campbell William , Hooks Gareth , Bradley Neil , Hill Arnold D. K. , Cassidy John T. , Boland Michael , Burke Paul , Nally Deirdre M. , Hill Arnold D. K. , Khogali Elmoataz , Shabo Wael , Iskandar Edrin , McEntee Gerry P. , O’Neill Maeve A. , Peirce Colin , Lyons Emma M. , O’Sullivan Adrian W. , Thakkar Rohan , Carroll Paul , Ivanovski Ivan , Balfe Paul , Lee Matthew , Winter Des C. , Kelly Michael E. , Hoti Emir , Maguire Donal , Karunakaran Priyadarssini , Geoghegan Justin G. , McDermott Frank , Martin Sean T. , Cross Keith S. , Cooke Fiachra , Zeeshan Saquib , Murphy James O. , Mealy Ken , Mohan Helen M. , Nedujchelyn Yuwaraja , Ullah Muhammad Fahad , Ahmed Irfan , Giovinazzo Francesco , Milburn James , Prince Sarah , Brooke Eleanor , Buchan Joanna , Khalil Ahmed M. , Vaughan Elizabeth M. , Ramage Michael I. , Aldridge Roland C. , Gibson Simon , Nicholson Gary A. , Vass David G. , Grant Alan J. , Holroyd David J. , Jones M. Angharad , Sutton Cherith M. L. R. , O’Dwyer Patrick , Nilsson Frida , Weber Beatrix , Williamson Tracey K. , Lalla Kushik , Bryant Alice , Carter C. Ross , Forrest Craig R. , Hunter David I. , Nassar Ahmad H. , Orizu Mavis N. , Knight Katrina , Qandeel Haitham , Suttie Stuart , Belding Rowena , McClarey Andrew , Boyd Alan T. , Guthrie Graeme J. K. , Lim Pei J. , Luhmann Andreas , Watson Angus J. M. , Richards Colin H. , Nicol Laura , Madurska Marta , Harrison Ewen , Boyce Kathryn M. , Roebuck Amanda , Ferguson Graeme , Pati Pradeep , Wilson Michael S. J. , Dalgaty Faith , Fothergill Laura , Driscoll Peter J. , Mozolowski Kirsty L. , Banwell Victoria , Bennett Stephen P. , Rogers Paul N. , Skelly Brendan L. , Rutherford Claire L. , Mirza Ahmed K. , Lazim Taha , Lim Henry C. C. , Duke Diana , Ahmed Talat , Beasley William D. , Wilkinson Marc D. , Maharaj Geta , Malcolm Cathy , Brown Timothy H. , Al-Sarireh Bilal , Shingler Guy M. , Mowbray Nicholas , Radwan Rami , Morcous Paul , Wood Simon , Kadhim Abbas , Stewart Duncan J. , Baker Andrew L. , Tanner Nicola , Shenoy Hrishikesh , Hafiz Shazia , De Marchi Joshua A. , Singh-Ranger Deepak , Hisham Elzanati , Ainley Paul , O’Neill Stephen , Terrace John , Napetti Sara , Hopwood Benjamin , Rhys Thomas , Downing Justine , Kanavati Sam , Coats Maria , Aleksandrov Danail , Kallaway Charlotte , Yahya Salama , Weber Beatrix , Templeton Alexa , Trotter Martin , Lo Christina , Dhillon Ajit , Heywood Nick , Aawsaj Yousif , Hamdan Alhafidz , Reece-Bolton Obuobi , McGuigan Andrew , Shahin Yousef , Aymon  , Luther Ali Alison , Nicholson James A. , Rajendran Ilayaraja , Boal Matthew , Ritchie Judith 
Published: January 2018

Abstract
Background
The ability to accurately predict operative duration has the potential to optimise theatre efficiency and utilisation, thus reducing costs and increasing staff and patient satisfaction. With laparoscopic cholecystectomy being one of the most commonly performed procedures worldwide, a tool to predict operative duration could be extremely beneficial to healthcare organisations.

Methods
Data collected from the CholeS study on patients undergoing cholecystectomy in UK and Irish hospitals between 04/2014 and 05/2014 were used to study operative duration. A multivariable binary logistic regression model was produced in order to identify significant independent predictors of long (> 90 min) operations. The resulting model was converted to a risk score, which was subsequently validated on second cohort of patients using ROC curves.

Results
After exclusions, data were available for 7227 patients in the derivation (CholeS) cohort. The median operative duration was 60 min (interquartile range 45–85), with 17.7% of operations lasting longer than 90 min. Ten factors were found to be significant independent predictors of operative durations > 90 min, including ASA, age, previous surgical admissions, BMI, gallbladder wall thickness and CBD diameter. A risk score was then produced from these factors, and applied to a cohort of 2405 patients from a tertiary centre for external validation. This returned an area under the ROC curve of 0.708 (SE = 0.013, p < 0.001), with the proportions of operations lasting > 90 min increasing more than eightfold from 5.1 to 41.8% in the extremes of the score.

Conclusion
The scoring tool produced in this study was found to be significantly predictive of long operative durations on validation in an external cohort. As such, the tool may have the potential to enable organisations to better organise theatre lists and deliver greater efficiencies in care.