Title: Peri-articular tranexamic acid injection in total knee arthroplasty: A Randomized controlled trial

Transcription

1 Author s response to reviews Title: Peri-articular tranexamic acid injection in total knee arthroplasty: A Randomized controlled trial Authors: Piya Pinsornsak (Pinpiya2003@yahoo.com) Santi Rojanavijitkul (sandee.21@hotmail.com) Sukanis Chumchuen (sukanis@hotmail.com) Version: 1 Date: 24 May 2016 Author s response to reviews: Dear Knut Beitzel Thank you very much for considering our paper to publishing in BMC Musculoskeletal Disorder. Now we finish the process of manuscript revision as all reviewer s comment. Please you see the attach files, and if you have any questions about ours paper, please feel free to contact us at my pinpiya2003@yahoo.com Sincerely yours Piya Pinsornsak. MD. (Corresponding author) Associate Professor, department of orthopaedics, Thammasat university, Thailand Answer to reviewers BMSD-D Peri-articular tranexamic acid injection in total knee arthroplasty: A Randomized controlled trial Piya Pinsornsak, M.D.; Santi Rojanavijitkul, M.D.; Sukanis Chumchuen, M.D. BMC Musculoskeletal Disorders

2 Reviewer reports: Reviewer #1: General remarks: - No control group - how much blood loss without tranexamic acid? What is the mean blood loss after TKA in a comparable population ml? Please discuss. Answer: Line 224. The previous prospective randomized controlled trial study comparing intravenous tranexamic acid injection with placebo in the patients undergone TKA found estimate blood loss in drain of tranexamic acid group significantly less than control group ( ± 234 ml VS ± 421 ml, p < 0.001) - 750mg were injected - please describe the technique and precise the ml of fluid Answer: Line 128. In group 1, the patients received 750 mg of peri-articular tranexamic acid injection (Transamin ; OLIC Thailand Ltd, Bangkok, Thailand; 250 mg/5 ml, 15 cc total volume)(fig.1) at the soft tissue around medial capsule (5 ml), lateral capsule (5 ml) and around the quadriceps muscle (5 ml). - were there patients with longer need for drainage than 2 days? Answer: Line 138. No. The drain was recorded at 24, 48 hours, and removed at 48 hours from the end of the operation (after skin closure) in all cases. - where was the drain positioned? always only one drain? Answer : Line 133. One Privac drain (Primed Halberstadt Medizintechnik GmbH, Halberstadt, Germany) was positioned at the lateral gutter - reference list needs an update: latest reference dates from 2013 Answer : References were updated until 2016 Mistakes: - 78 there Answer : Line 78 Correction of capital letter There to there - 82 field Answer: Line 82 Correction filed to field

3 - 86 has to yet been clinically reported. Answer: Line 86 Correction is no clinical report before to has not yet been clinically reported - 90 were proven Answer: Line 90 Correction have been proven to were proven - 92 we Answer: Line 91 Correction We to we discharge criteria were that the patient was able to walk... Answer: Line147. Correction The discharge criteria was the patient ca8 walk with walking aid to The discharge criteria were that the patient was able to walk with walking aid safety Answer: Line 236 Correction safely to safety re-write sentence: Our study found Answer: Line 237 Our study found no VTE in either group, but there were too small number of patients for interpretation. Figures: - please add x-ray post-surgery as an example. Answer: Fig 2. added - Please add figure of peri-articular application Answer: Fig 1. added Reviewer #2: The general topic of this study is of timely importance and fits to the scope of the journal addressing musculoskeletal surgeons specialized in arthroplasty. Still postoperative bleeding in TKA with relevant complications such as hypovolemic shock and subsequent allogeneic blood transfusions displays a major problem in arthroplasty. Tranexamic acid is know to be an effective agent for reduction of blood loss following TKA. Intravenous

4 tranexamic acid injections showed satisfactory results but with the fear of systemic side-effects on venous thromboembolic events. Thus peri-articular injection of tranexamic acid is by principle a promising concept. Furthermore to my literature search it has not been reported before. However the study lacks the absolutely necessary control group (i.e. placebo w/o tranexamic acid). The authors state Since the administration of intravenous tranexamic acid is a standard protocol for our patients and with the possible problems with ethical issues, we decided not to establish a placebo group". Administration of tranexamic acid is not a must neither in european nor american arthroplasty recommendations. Thus rejection of the control group by your ethic committee is not imaginable. Thus I have to reject this work. However I would strongly suggest to evaluate a respective control group in the same setting used for the other two tranexamic acid groups and show the interested reader additionally the blood loss w/o the presence of any procoagulants. When doing so I would additionally suggest that a native english speaker looks over the manuscript in order to do necessary language corrections. Reviewer #3: Dear authors, thank you for your very interesting article. The publications deals with the use of topical transexamic acid (peri-articular injection) compared to the intravenous injection. I would recommend that you add your guidelines for blood transfusion (e.g. Hb below 10g/dl, clinical signs of anaemia). And maybe you can comment on your high blood Transfusion rate of nearly 30%. Also I would like to see a discussion with more recent literature (you have referred to 2 articles from 2013, all others are older). Answer : Line 140 Criteria for blood transfusion were the patients with hemoglobin less than 10 g/dl, or patients with any signs of anemia (chest pain that suggested from cardiac origin, congestive heart failure, and unexplained tachycardia or hypotension unresponsive to fluid replacement) at 24 or 48 hour. One packed red cells was transfused per 1 g/dl of hemoglobin drop. There are some wrong sentences: Line 78, 91 and 226. Answer: Line 78. change There to there

5 Line 91. change Because of to Because Line 236. change safely to safety