Statistician for a Clinical Study ( Retrospective data)

Basically we are looking at a certain procedure it is called paracentesis, which is used to drain fluid from the abdomen. In UK and most western countries the guidelines suggest to not keep the drain more than 6 hours to avoid complications mainly infection. This recommendation is not based on any strong data or research, it is mostly expert opinions. However in several countries the drain is left for more than that even for days. Including our patients. Therefore, we want to look at the complication rate of these drains in patients and whether the duration increase the rate of complications, including bleeding and infection. and whether the variants we had , including age, gender, past medical history, cause of the ascites play a role.
I would be grateful if you can send me your proposal on how you will run the statistical model. and as we would like to publish the study, we would expect that you will write the statistical methods and results for the article, and we would also like to continue to work together if we have any questions or requests from reviewers in relation to the statistical analysis.