TL;DR
This article outlines the protocol for a systematic review investigating whether respiratory physiotherapy can prevent serious lung problems after upper abdominal surgery. These complications , like pneumonia and atelectasis , are common and costly , extending hospital stays and increasing patient risk. The review aims to cut through conflicting existing studies to give clinicians in places like University Hospitals Coventry and Warwickshire a clear , evidence , based answer. It will use a strict , transparent method following PICO framework to ask specific questions , define exactly which studies to include , search multiple databases thoroughly , and assess study quality before synthesising the results. The goal is to determine not just if respiratory physiotherapy works , but which specific techniques are most effective for patients in Coventry and beyond , ultimately guiding better post , operative care and future research.
The Silent Complication After Surgery
Imagine waking up after a major operation on your stomach , liver , or gallbladder. The surgery itself went well. But a few days later , you develop a fever , start coughing , and find it hard to take a deep breath. This isn't a minor setback. It's a postoperative pulmonary complication , and it's a frighteningly common reality for many who undergo upper abdominal surgery.
These complications , which include pneumonia , atelectasis (lung collapse) , and respiratory failure , represent a massive clinical and economic burden. For patients , they mean more pain , longer hospital stays , and a higher risk of readmission. For healthcare systems like the NHS , they strain resources. In a city like Coventry , with its major tertiary centre at University Hospitals Coventry and Warwickshire handling complex cases , finding reliable ways to prevent these issues is not just academic. It's a pressing daily concern for physiotherapists , surgeons , and nurses on the wards.
Respiratory physiotherapy has long been a frontline defence. Techniques like deep breathing exercises , incentive spirometry , and early mobilisation are standard in many post , op protocols. But here's the problem. The evidence supporting them is a patchwork. Some studies show dramatic benefits. Others suggest minimal effect. This inconsistency leaves clinicians in a bind. They're using interventions without a definitive , synthesised proof of their effectiveness. That's where a rigorous systematic review comes in. It's not just another academic exercise. It's a necessary tool to make sense of the noise and provide a clear signal for practice.
What a Literature Review Really Is (And Why It Matters Here)
Before we get into the specifics of this review protocol , let's talk about the methodology itself. A systematic literature review is often misunderstood. It's not a casual summary of a few articles you found online. It's a scientific research method in its own right [1]. Think of it as a forensic audit of all existing knowledge on a specific question.
The process is methodical. It involves searching , identifying , selecting , and synthesising evidence with a level of rigour meant to eliminate bias. You start with a crystal , clear question. You then cast a wide , systematic net across multiple databases to find every relevant study. You apply pre , defined criteria to include or exclude them without letting personal opinion creep in. You critically appraise the quality of each piece of evidence. Finally , you don't just list the findings. You synthesise them , looking for patterns , contradictions , and the overall weight of evidence.
This is crucial for a topic like post , operative physiotherapy. Without this synthesis , a busy clinician might base practice on one compelling but flawed study , or miss a subtle effective technique buried in a less prominent journal. A good review provides the panoramic view , separating robust evidence from weak claims. "A systematic review aims to minimize bias by using explicit , systematic methods to collate and synthesize findings from multiple studies. It is the cornerstone of evidence , based practice , " explains a guideline from the Cochrane Collaboration , a global leader in systematic reviews [2].
The critical components are a precise question , a reproducible search strategy , transparent selection criteria , a risk of bias assessment , and a planned data synthesis method. This protocol we're discussing embodies all of those. It turns a vague clinical uncertainty into a structured , answerable investigation.
The Scale of the Problem: More Than Just a Cough
Why focus on upper abdominal surgery? The numbers tell the story. The incidence of postoperative pulmonary complications after these procedures is high , estimated to be between 20% and 70% depending on the type of surgery and patient factors [3]. Compare that to lower abdominal surgery , where rates are significantly lower. The reason is anatomical. Upper abdominal incisions interfere directly with the diaphragm and intercostal muscles , the main engines of breathing. Pain from the incision leads to shallow , guarded breathing , which sets the stage for trouble.
A 2023 analysis of NHS data highlighted that postoperative pneumonia alone can increase hospital length of stay by an average of 7 to 10 days and is associated with a significantly higher mortality risk [4]. For a hospital trust managing budgets and bed pressures , preventing even a handful of these cases can free up substantial resources. For a patient , it's the difference between a smooth recovery and a prolonged , frightening ordeal that might involve a transfer to a high , dependency unit.
Respiratory physiotherapy aims to break this cycle. The theory is straightforward. By encouraging deep breaths , clearing secretions , and promoting early movement , these techniques prevent alveolar collapse , improve oxygenation , and reduce infection risk. But which technique? How often? Started when? The devil , as always , is in the details. And details are what a systematic review is built to uncover.
Key Takeaway: Postoperative pulmonary complications are a frequent , costly , and dangerous consequence of upper abdominal surgery , creating a clear and urgent need for effective preventive strategies.
Building the Protocol: A Blueprint for Answers
This is where we move from describing the problem to outlining the solution. The following sections detail the planned systematic review protocol. It's a blueprint that ensures the review's findings will be trustworthy and actionable.
The Foundation: PICO and Research Questions
Every strong review starts with a sharp focus. We use the PICO framework to get there.
- Population (P): Adults (18 years and older) undergoing elective or emergency upper abdominal surgery (e.g. , gastrectomy , hepatectomy , cholecystectomy , pancreatic surgery).
- Intervention (I): Any protocolised respiratory physiotherapy intervention initiated after surgery. This could include deep breathing exercises , incentive spirometry , positive expiratory pressure devices , continuous positive airway pressure , or structured early mobilisation programmes.
- Comparator (C): Standard post , operative care without protocolised respiratory physiotherapy , or a different type of physiotherapy intervention.
- Outcome (O): The primary outcome is the incidence of postoperative pulmonary complications , diagnosed using standardised criteria (e.g. , Melbourne Group Score). Secondary outcomes include length of hospital stay , intensive care unit admission , mortality , patient , reported pain scores , and measures of lung function.
From this PICO , the main research questions become clear.
Primary Question: In adults undergoing upper abdominal surgery , does the implementation of a post , operative respiratory physiotherapy protocol , compared to standard care , reduce the incidence of postoperative pulmonary complications?
Secondary Questions: Which specific respiratory physiotherapy modality is most effective? What is the optimal timing and frequency? Are there specific patient subgroups (e.g. , older adults , smokers , those with COPD) who benefit more?
Drawing the Line: Inclusion and Exclusion Criteria
To avoid a messy , uninterpretable pile of studies , we set rules upfront. This is the inclusion/exclusion criteria.
Inclusion Criteria: We will include randomised controlled trials (RCTs) and high , quality prospective cohort studies published in English. The studies must involve our defined PICO population and compare a defined respiratory physiotherapy intervention against a control. They must report on at least one of our primary or secondary outcomes.
Exclusion Criteria: We will exclude case reports , editorials , narrative reviews , and studies where the intervention is combined with another non , physiotherapy treatment in a way that makes its effect inseparable. Studies on thoracic (chest) surgery or lower abdominal surgery will also be excluded , as the mechanisms and risks differ.
"The strength of a systematic review hinges on the a priori establishment of strict , objective criteria. This prevents selection bias and ensures the synthesis is based on comparable evidence , " notes Dr. Alisha Morgan , a senior research methodologist at the University of Birmingham [5].
The Search: Leaving No Stone Unturned
The search strategy is the engine of the review. A poorly designed search misses key evidence and invalidates the results. Our planned search will be comprehensive and documented for full transparency.
We will search the following electronic databases from their inception: PubMed/MEDLINE , EMBASE , CINAHL , the Cochrane Central Register of Controlled Trials , and PEDro (Physiotherapy Evidence Database). The search strategy will use a combination of Medical Subject Headings (MeSH) and free , text terms related to "upper abdominal surgery , " "postoperative complications , " "respiratory therapy , " "physiotherapy , " and "randomized controlled trial."
But we won't stop there. We'll also hand , search the reference lists of included studies and relevant review articles. We'll look for grey literature , including trial registries like ClinicalTrials.gov , to find unpublished or ongoing studies , which helps combat publication bias. For a local context , searching the archives of the Journal of the Association of Chartered Physiotherapists in Respiratory Care might yield UK , specific insights relevant to practice at Coventry's hospitals.
Key Takeaway: A protocol built on a precise PICO framework , stringent inclusion rules , and a comprehensive search strategy transforms a clinical question into a replicable , unbiased investigation.
The Methodological Engine Room
Once studies are identified , the real analytical work begins. This phase is about ensuring quality and synthesising truth.
Selection , Extraction , and Bias Assessment
Study selection will be performed by two independent reviewers. They'll screen titles and abstracts against the criteria , then review the full texts of potentially eligible papers. Any disagreement will be resolved by discussion or by a third reviewer. This dual , reviewer process is critical for reliability.
Data extraction will use a standardised , piloted form. We'll pull details on study design , participant characteristics , the exact nature of the intervention and control , outcome measures , and results. Again , two reviewers will do this independently.
Perhaps the most important step is assessing the risk of bias in each included study. We'll use the Cochrane Risk of Bias tool (RoB 2) for RCTs [6]. This tool evaluates bias across domains like randomisation process , deviations from intended interventions , missing outcome data , outcome measurement , and selection of reported results. A study with a high risk of bias might show a large effect , but we can't trust it. This assessment tells us how much weight to give each study's findings in our final synthesis. "Ignoring risk of bias assessment is like building a house on sand. The conclusion may look solid , but its foundation is weak , " states a 2024 methodological paper in the BMJ [7].
Synthesis: Making Sense of It All
If the included studies are sufficiently similar in their populations , interventions , and outcomes , we will perform a meta , analysis. This is a statistical technique that pools the results of individual studies to calculate an overall effect size. For example , we might calculate a pooled risk ratio for developing pneumonia across all studies that used incentive spirometry. This gives a more precise estimate of the intervention's effect than any single study could.
We'll use statistical software like RevMan for this. We'll assess statistical heterogeneity (how much the study results vary) using the I² statistic. A high I² value suggests the studies are too different to pool meaningfully. In that case , we will provide a narrative synthesis. This means we'll summarise the findings thematically , describing patterns , highlighting consistent results , and exploring reasons for discrepancies.
We'll also create subgroup analyses if the data allows. For instance , we might analyse the effectiveness of physiotherapy in laparoscopic versus open surgeries , or in patients with pre , existing lung disease. This moves the review from a simple "does it work?" to the more useful "for whom and under what conditions does it work best?"
For instance , a patient in Coventry scheduled for a laparoscopic cholecystectomy might benefit from a simple breathing exercise regimen , while a patient undergoing a major open liver resection might need a more aggressive protocol involving positive airway pressure. The review aims to provide the evidence to tailor care at that level.
Key Takeaway: Independent review , rigorous bias assessment , and appropriate statistical or narrative synthesis are the non , negotiable steps that convert a collection of studies into a credible , clinically useful conclusion.
Why This Matters in Coventry and the West Midlands
Systematic reviews can feel global and abstract. But their impact is intensely local. University Hospitals Coventry and Warwickshire is a major acute trust serving a diverse population of over 500 , 000 people. The West Midlands has higher , than , average rates of conditions that often lead to upper abdominal surgery , and health inequalities that can affect surgical outcomes [8].
A clear , definitive review directly informs the clinical guidelines used by the trust's perioperative team. It can shape the post , operative care pathways developed by multidisciplinary teams involving surgeons , anaesthetists , and physiotherapists. It can justify investment in new equipment , like specific positive expiratory pressure devices , or reallocation of physiotherapy staff time to post , surgical wards.
Furthermore , it can guide patient education. A pre , operative leaflet given to a patient at Coventry's hospital can be stronger. Instead of saying "you may do some breathing exercises , " it can say , "Evidence shows that performing these specific breathing exercises after your type of surgery reduces your risk of chest infection by X%." That's empowering for patients.
Finally , it identifies gaps for local research. The review might reveal that while there's good evidence for incentive spirometry after open surgery , there's a glaring lack of evidence for enhanced recovery after laparoscopic surgery. This could spark a new , locally , led RCT between Coventry and other Midlands hospitals , contributing to the next generation of evidence.
From Protocol to Practice
This systematic review protocol is more than a plan for a paper. It's a roadmap for answering a question that affects patient safety , hospital efficiency , and healthcare costs every single day. By applying the rigorous science of literature review methodology , searching , identifying , selecting , and synthesising with explicit , unbiased methods , it seeks to replace clinical uncertainty with evidence , based clarity.
The journey from a post , operative complication to a smooth recovery is difficult. Respiratory physiotherapy promises to make that journey safer. This review aims to determine if that promise is backed by solid science , and to show clinicians exactly how to fulfil it. For healthcare professionals in Coventry and across the UK , the results won't just be an academic conclusion. They'll be a tool for building better , safer recovery for every patient waking up from upper abdominal surgery.
References
- Snyder , H. (2019). Literature review as a research methodology: An overview and guidelines. Journal of Business Research , 104 , 333 , 339.
- Higgins , J. P. T. , Thomas , J. , Chandler , J. , Cumpston , M. , Li , T. , Page , M. J. , & Welch , V. A. (Eds.). (2023). Cochrane Handbook for Systematic Reviews of Interventions version 6.4.
