Review for 10.1186/s12876-019-1028-7 (2019)

Reviewer ’s report  
 
Title:  Is Discard Better than Return Gastric Residual Aspirates: A Systematic Review and M eta-
analysis  
 
Version: 0 Date: 18 Jan 2019 
 
Reviewer:  Lyvonne N.  Tume  
 
Reviewer’s report:  
 
Dear author/s,  
 
Thank you for your systematic review on returning vs discarding GRV. I have some feedback to 
strenghthen your manuscri pt. 
 
Early on in the paper and in the nmethods and in your conclusion you need to make it very clear 
your age criteria, i can see that this is adults only so this should be specifiied throught  the paper 
and in the methods.  
 
Please avoid the term prognosis throughout, what you mean is imporved 'outcomes' and the 
sentence the mangement of gastrisc aspirates (GA) is not essential to prognosis, please revise this 
to something like: The assessment of gastric residual volume (GRV) is common practice in 
critical c are units.  
 
I think you have used 'et al' throughout the paper to mean 'etc' neither of these should be used in 
this paper,  
 
In general you this paper and the english wording/writing needs review by a native English 
speaker, it is poorly worded in many parts, and needs revision.  
 
What are episodes of gastric emptying delay? I think you mean delayed gastric emptying - but 
you nee d to describe how these papers measured this - because this term and outcome is often 
used in different ways and it is not clear if all your papers defined this in the same way.  
 
In the consluion of your abstract remove the word 'solid' and your concluding  sentence - impact 
on what outcomes? please state  
 
I would suggest a key word should be gastric residual volume.  
 
Background - this section needs extensive english editing and correcting and the sentences are 
too long and need to be shortened. Again use th e word 'outcomes' not prognosis.  
 
References 7 -9 do not imply this - they have actually questioned the evidence for this procedure.  
 
 
Methods  
 
Again make it clear in which patients (adult critically ill) this review included - this should be 
clear in the inclu sion and exclusion criteria as there is work in neonatal patients.  
 
 
Results  
 
In your forrest plot, for the outcome episodes of - revise wording  to delayed gastric emptying - 
but we need to know in the results how these outcome were defined in the papers... this was is 
very ambiguous.  
 
 
Discussion  
 
Again requires extensive english editing.  
 
There is no discussion of the value and importance of gastric aspirate appearance as a significant 
factor in the decision making to return or discard. This is a well known is sue. Discarding risks 
reducing the energy intake but very abnornal looking aspirates: bloody, fecal or very bilious are 
virtually always discarded and there should be some discussion around this.  
 
Your sentence that "different individuals have different to lerance to GRV" does not make sense, 
it is not that different indivduals have a different response it is that different criticaly ill patients 
have differening levels of gut dysfunction depdnant on their pathology, shock states or therpaies 
applied that re duce/impair gut motility - please remove your sentence and discuss this.  
 
Your references 10 and 23 are very old and since then there is a propsective study in children 
Martinez et al 2017 'Gastric emptuing in critically ill children) in PCCM that shows tha t delayed 
gastric emptying (measured by the paracetamol absrorbtion test) in criticallly ill children had NO 
relationship to GRV - some patients with delayed GE had high GRVs but others did not.  
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
No 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
Yes 
 
Are the conclusions drawn adequately supported by the data shown?  
If not, please explain in your comments to the authors.  
 
Yes 
Are you able to assess any statistics in the manuscript or would yo u recommend an 
additional statistical review?  
If an additional statistical review is recommended, please specify what aspects require further 
assessment in your comments to the editors.  
 
I am able to assess the statistics  
 
Quality of written English  
Please in dicate the quality of language in the manuscript:  
 
Needs some language corrections before being published  
 
Declaration of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
 
1. Have you in the past five years received reimbursements, fees, funding, or salary from an 
organisation that may in any way gain or lose financially from the publication of this 
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation that may in any way gain or lose 
financially from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying for any patents relating to the content of the 
manuscript?  
 
4. Have you received reimbursements, fees, funding, or salary from an organization tha t 
holds or has applied for patents relating to the content of the manuscript?  
 
5. Do you have any other financial competing interests?  
 
6. Do you have any non -financial competing interests in relation to this paper?  
 
If you can answer no to all of the above, wri te 'I declare that I have no competing interests' 
below. If your reply is yes to any, please give details below.  
 
Nil 
 
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