A study to analyze the effectiveness of incentive spirometry versus deep breathing exercises and incentive spirometry in preventing post operative pulmonary complications in coronary bypass grafting patients – A experimental study: Dr.Sathiya Seelan K., M.P.T., Vice Principal & Professor of Physiotherapy, PES College of Physiotherapy, Kuppam, Andhra Pradesh, India; 1 Dr.Kurapati Madhava Reddy, Ph.D., D.Sc., Professor & Principal, Sri Lakshmi Institute of Medical Sciences College of Physiotherapy, Kavali, Andhra Pradesh, India.2
Background:
Cardiovascular diseases have now become the leading cause of death in India. The global burden of disease estimate of age-standardized CVD death rate of 272 per 100,000 is higher than the global average of 235 deaths per 100,000. Coronary artery disease has reached epidemic proportions in Southeast Asia, particularly India, in recent years (Sachin Chaudhary et al 2020). CABG is performed daily worldwide on patients with coronary artery disease.
Coronary artery bypass grafting (CABG) is a surgical procedure that involves bypassing blocked coronary arteries with the objective of restoring blood flow to the heart (Zerang F et al 2022). Patients who have undergone cardiac surgery are at an elevated risk of developing postoperative pulmonary complications (PPCs) (Fischer MO et al 2022). Furthermore, approximately one-quarter of patients who have undergone cardiac surgery and do not have chronic pulmonary dysfunction develop a PPC. PPCs range from a mild respiratory infection to acute respiratory failure, which may necessitate the use of oxygen therapy and invasive or non-invasive mechanical ventilation (MV) support (Ball L et al 2022). PPCs have been demonstrated to result in elevated healthcare expenditures (Sameed M et al 2021), extended periods of hospitalisation, and an increased prevalence of morbidity and mortality (Ball L et al 2022). The development of a PPC is influenced by a number of factors. Contributing factors have included surgical stress and anaesthesia, the systemic inflammatory response and oxidative stress from cardiopulmonary bypass, the type of surgery performed, inadequate pain management, the anaesthesia protocol employed, the use of blood products, and diaphragmatic dysfunction (Zerang F et al 2022).
Pulmonary complications in the period immediately following coronary artery bypass grafting (CABG) are a cause of morbidity. Patients with preexisting pulmonary disease have been reported to be at increased risk for complications following surgery (Brooks et al 1995, Dales RE et al 1993, Gass GD et al 1986). By contrast, Warner et al 1982 reported no increased risk following coronary artery bypass grafting. A significant contributing factor to the development of PPCs is preoperative respiratory muscle weakness (Assouline B et al 2021). A variety of respiratory physiotherapy techniques are employed with the objective of alleviating muscle weakness and preventing PPCs in patients who have undergone cardiac surgery.
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The main aims of respiratory physiotherapy are to improve ventilation-perfusion compliance, increase lung volumes, improve mucociliary clearance, and reduce pain (Lahoud R et al 2021). The most commonly used methods are incentive spirometry (IS) and deep breathing exercises (DBE), which are easy to use, straightforward, and inexpensive. IS is a method that provides visual feedback based on the patient’s motivation and cooperation in deep breathing (Zerang F et al 2022) to maintain alveolar patency after cardiac surgery (Narayanan LT et al 2020), improve lung volumes by ensuring oxygen delivery and proper ventilation (Zerang F et al 2022, Narayanan LT et al 2020), ensure maximum bronchial dilatation, and produce an effective cough (Zerang F et al 2022). In clinical practice, DBEs with IS is usually initiated in the post-operative period (Alwekhyan SA et al 2022). However, it has been reported that inadequate physical adaptation and respiratory muscle weakness in the preoperative period are closely associated with PPCs leading to a prolonged hospital stay and increased mortality (Assouline Bet al 2021).
The effectiveness of physical therapy when provided routinely for patients following coronary artery bypass grafting (CABG) has not been proven to be effective in decreasing morbidity. Jenkins et al 1983 concluded that the addition of breathing exercises or incentive spirometry (IS) to early ambulation, forced expiratory maneuvers, and coughing conferred no additional benefits to their patient population, whose average preoperative spirometric data indicated no airflow limitations.
Stiller et al 1994 studied patients whose preoperative spirometric data indicated no airflow limitations and reported that preoperative education, postoperative deep breathing exercises, and forced expiration manoeuvres were not effective in reducing morbidity. Study by Johnson et al 1995 did not provide sufficient spirometric data to allow determination of whether their patients had airflow limitations. They reported that for those patients with minimal atelectasis at the time of extubating, the addition of sustained maximal inflations (SMI) to a routine of education, early ambulation, and deep breathing exercises did not reduce morbidity. The outcomes of those patients with marked atelectasis at the time of extubating were not improved by the addition of percussion to a regimen of ambulation, deep breathing exercises, and sustained maximal inflations (SMI). Incentive spirometry is used frequently as a component of postoperative pulmonary management. Studies evaluating the effectiveness of incentive spirometry in patients who have had cardiac surgery, however, have been unable to demonstrate the superiority of incentive spirometry (IS) over breathing exercise, early mobilization (Jenkins SC et al 1989, Kannel WB et al 1981, Habib MP et al 1990, Dull JL et al 1983) or intermittent positive pressure breathing (Gale GD et al 1980, Oikkonen M et al 1991, Iverson LIG et al 1978). In contrast, Oulton et all compared the use of physical therapy alone with the use of physical therapy and each of two incentive spirometers and found that the group using a device requiring a preset volume goal had superior results.
In order to prevent or diminish postoperative complications Physiotherapy treatment is often prescribed to patients undergoing cardiac surgery, the physiotherapy treatment generally consists of early mobilization, range of motion exercises during the hospital stay (E. Westerdahl et al 2011). Early mobilization and physical activity are often the first choice of treatment, but evidence as to the optimal intensity, timing and choice of exercises is scarce. There are only limited published data on how the cardiac surgery patient should be mobilized and exercised during the first
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postoperative period in hospital (Cockram J et al 1989, Hirschhorn AD et al 2008, Jenkins SC et al 1986).
After coronary artery bypass grafting physiotherapy-consisting of breathing exercises emphasising inspiration, incentive spirometry, techniques to clear bronchial secretions, and early mobilization is given with the aim of increasing lung ventilation and preventing chest infections (Dunstan Jet al 1997). Recently, changes to the post
operative care of cardiac surgery patients have been advocated. Patients could be managed using “rapid recovery guidelines” without compromising patient outcomes or levels of satisfaction (Reyes A et al 1997). Early extubating (7-11 hours postoperatively) following cardiac surgery resulted in a decrease in length of intensive care unit (ICU) stay and no increase in clinically important postoperative complications (Stafford R et al 1997).
Mueenudheen Tp et al 2012 Conducted a study to compare the effects of Incentive spirometry and deep breathing exercise on pulmonary functions after uncomplicated coronary artery bypass surgery and the study concluded that deep breathing exercises and incentive spirometry are of equal effect provided the patients do not have any complication after coronary artery bypass surgery.
There are limited studies investigating the efficacy of preoperative IS application only in patients undergoing open-heart surgery (Moradian ST et al 2019, Sweity EM et al 2021). In addition, the literature evaluating the effect of IS and DBEs on respiratory complications in patients undergoing open-heart surgery is inconsistent. Some studies have found a statistically significant lower incidence of atelectasis with IS and DBEs (Sweity EM et al 2021, Oshvandi K et al 2020, Nardi P et al 2019), while others have found no effect (Freitas ER et al 2012, Overend TJ et al 2001, Moradian ST et al 2019).
A study to analyze the effectiveness of incentive spirometry versus deep breathing exercises and incentive spirometry in preventing post operative pulmonary complications in coronary bypass grafting patients. It is anticipated that the data obtained from this study will contribute to the existing literature on the effects of initiating IS and DBE in the preoperative and postoperative period in patients undergoing CABG. Furthermore, it may shed light on preoperative Physiotherapy practices to prevent PPCs.
Aims & Objectives: A study to analyze the effectiveness of incentive spirometry versus deep breathing exercises and incentive spirometry in preventing post operative pulmonary complications in coronary bypass grafting patients – A experimental study.
Method: An experimental design involving pre and post-test analysis with two groups Group A and Group B by using Simple random sampling technique on 30 subjects with 15 subjects in Group A and 15 subjects Group B with the age ranged between (40-60) years with a mean of 50.93 ± 10.71 years in group A and 50.33 ± 10.60 years in group B subjects were recruited from Intensive care unit of PES Institute of Medical Sciences and Research, Kuppam, Chittoor District, Andhra Pradesh based on the inclusion and exclusion criteria and the study procedures were explained to the subjects and informed consent was obtained prior to study. Before starting the training session pre – test scores were measured by using a computerized spirometer.
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Group A Subjects (n=15) received controlled diaphragmatic breathing exercise as part of deep breathing exercise along with Incentive Spirometry; and subjects in Group B (n=15) received incentive spirometry alone. At the initial session, the subject’s demographic data, resting systolic blood pressure (SBP) and diastolic blood pressure (DBP) in comfortable crook lying position were measured by using a sphygmomanometer. Forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were measured in comfortable crook lying position through computerized spirometer. The highest values taken from three satisfactory attempts which were recorded are used to calculate the forced expiratory ratio (FEV1/ FVC).
Subjects in Group A were asked do the deep breathing exercise 10 times per session with 5 relaxed diaphragmatic breathing with a rest period of 1 minute in between, and trained for four times daily for 7 days followed by Incentive Spirometry 10 times per session with a rest period of 1 minute between each session, and trained for four times daily for 7 days and the approximate duration of the session is 40 minutes.
Subjects in Group B were asked do Incentive Spirometry 10 times per session with a rest period of 1 minute between each session, and trained for four times daily for 7 days and the approximate duration of the session is 30 minutes.
Both groups were be encouraged to perform ankle circumduction, range of motion of all extremities, three maximal supported coughs; encouragement and assistance to turn from side to side, sit up and stand up during the rehabilitation program.
The outcome was measured as pretest before the surgery and 4, 12, 24, 72 hours after the surgery and 4 times a day for 7 days as a post test measure for all the subjects by using Forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) as the outcome measures by using computerized spirometer. The pretest and post-test values were considered for data analysis to infer the results and the data was analyzed using various statistical measures such as mean, standard deviation and tests of significance such as Paired ‘t’ test and Wilcoxon Signed Rank Test. Statistical analysis for the present study was done manually as well as using the statistics software SPSS 15 version so as to verify the results obtained. Nominal data from patient’s demographic data i.e. age, sex distribution were analyzed using student ‘t’ test. Intra group comparison of the pre interventional and post interventional outcome measures was done by using paired ‘t’ test and whereas Wilcoxon Signed Rank test was used to measure the inter group difference. Probability values less than 0.05 were considered statistically significant and probability values less than 0.001 were considered highly significant
Results:
The study result shows that the post
interventional value of FEV1 was 41.07 ±
9.17 and 35.87 ± 7.18 (t=0.905, p=0.369) in
group A and B respectively. The mean for
above values is 12.03 ± 4.32 and 16.82 ±
6.38 (t=0.126, p=0.900) in Group A and
Group B respectively. This shows a is
significant increase in mean value of FEV1
post interventionally in Group A who was treated with controlled diaphragmatic breathing exercise as part of deep breathing exercise along with incentive spirometry (t=0.126, p=0.900) compared to group treated with Incentive Spirometry alone and it was supported by the studies conducted by Haeffener MP et al (2008), Herdy AH et al (2008), Isabel Yanez Brage, et al (2009) and Seyed Kazem Shakouri et al (2015).
The post-interventional value of FVC is 40.47 ± 8.78 and 37.27 ± 6.37 (t=0.901, p=0.293) in group A and B respectively. The mean for above values is 13.86 ± 3.92 and 19.33 ± 5.81 (t=0.121, p=0.900) in Group A and Group B respectively. There is significant increase in mean value of FVC post interventionally in Group A treated with controlled diaphragmatic breathing exercise as part of deep breathing exercise along with spirometry (t=0.121, p=0.900) compared to group B treated only with
Incentive Spirometry and it was supported by Westerhl et al (2005 ) and Orfanos T et al (2008) which concluded that breathing exercise cause significant increase in both tidal volume and respiratory rate; Further the study conducted by Oshvandi K et al 2020 that breathing exercises can reduce the incidence of atelectasis; and Study conducted by Muhammad Nouman Hussain et al shows that out of all the 40 patients 26 (65%) were males and 14 (35%) were females with the mean age of 53±7.9 years in conventional and 56±5.9 years in group performing ACBTs. There was significant improvement in Forced Expiratory Volume (FEV1) and chest expansion (p≤0.05) of ACBT group.
However, within group analysis revealedsignificant improvement in all parameters of both groups (p<0.01) and the study concluded that controlled diaphragmatic breathing along with incentive spirometry has beneficial effects in improving FEV1 and chest expansion as compared to Incentive spirometry and traditional physical therapy in post CABG patients during phase I of cardiac rehabilitation which supports the outcome of this study; Further the results of the study by Begum
Affrin Zaman et al 2016 showed that the value of F = 45.729 to find the difference in PEFR in Group B is significant (p=0.00). It has been found that PEFR increased significantly after application of incentive spirometer with EPAP to the patients after 4th day. On Day 4, t = 3.750, which is significant (p = 0.001) implying that deep breathing exercise with PEP device is more effective to increase PEFR as compared to incentive spirometer with EPAP and the study concluded that PEP device is more effective than Incentive Spirometry with EPAP in preventing postoperative complications following CABG surgery. It can be inferred that deep breathing exercise with PEP device is more effective than incentive spirometer with EPAP in improving SPO2 and PEFR in both the groups.
Even though the FVC and FEV1 in Group B who used incentive spirometry shows less significance compared to deep breathing exercise Group A, FVC and FEV1 values in group B predicts that incentive spirometry can also be used to prevent pulmonary complications following coronary artery bypass grafting along with diaphragmatic breathing exercise and it was supported by the studies conducted by Soutar et al (1988 ) and Jan L. Dull et al (1983); Further the results of the study by Abdullah Ibn Abul Fazal et al 2023 concluded that Incentive Spirometry (IS) is not superior to other conventional physiotherapy techniques, but when used in combination, it can be used as the most effective treatment technique for patients who have undergone coronary artery bypass grafting; The results of the study by Fatemeh Zerang et al 2022 shows that the mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) on the first day after the intervention in patients undergoing the IS group was significantly higher than the DBE group (p<0.05). On the third day after the intervention, the mean arterial oxygen saturation (SaO2) in patients of the IS group was significantly higher than the DBE group and the mean respiratory rate (RR) in patients in the IS group was significantly lower than the DBE group (p <0.05). However, there was no significant difference between the two groups in terms of other indices (p> 0.05) and the study concluded that IS has a greater effect on hemodynamic and oxygenation indices of patients undergoing CABG compared to DBE, so, it is recommended to use IS to improve hemodynamic and oxygenation indices in these patients; Study by Jadeel Noor Faleh et al 2022 showed that Patients in the intervention group had a lower incidence of postoperative pulmonary complications compared to the control group (12.5% and 21.8%). There was a statistically significant difference between the two groups regarding postoperative PEFR, HLOS and intensive care unit stay and the study concluded that Preoperative rehabilitation (involving incentive spirometer is related to a lower incidence of postoperative pulmonary complications for the group that received the intervention. Training with preoperative incentive spirometer resulted in a shortening of hospital length of stay and Intensive Care Unit (ICU) stay.
This study implies that controlled diaphragmatic breathing exercise as deep breathing exercise regime along with incentive spirometry is more efficient than using incentive spirometry alone in improving lung volume, forced vital capacity (FVC), forced expiratory volume in one second (FEV1) and can be used postoperatively in preventing pulmonary complications following coronary artery bypass grafting patients; and it was supported by the study conducted by Essa M. Sweity et al 2021 concluded that that preoperative incentive spirometry for two days along with the exercise of deep breathing, encouraged coughing, and early ambulation following CABG are in connection with prevention and decreased incidence of atelectasis, hospital stay, mechanical ventilation duration and improved postoperative oxygenation with better pain control. A difference that can be considered both significant and clinically relevant; Hatice Oner Cengiz et al 2025 concluded that deep breathing exercises with an incentive spirometer initiated in the preoperative period contribute to a reduction in postoperative pulmonary complication rates, shortening of mechanical ventilation time, length of stay in the intensive care unit, length of hospital stay, and improvement of pre- and postoperative oxygenation; Manoj et al 2023 concluded that Acapella and Incentive spirometry both have beneficiary effects on oxygen saturation (Spo2), Pulse rate and arterial blood pressure in post coronary artery bypass grafting but statistically Acapella give more significant improvement than Incentive spirometry; Fatima et al 2021 reported from the study that the Mean pO2
(mmHg) at day 1 & day 4 was 136±23.04 & 74.42±16.22 respectively in group-A (p<0.001) as compared to 127.96 ±16.99 & 70.80±10.89 respectively in group-B (p<0.001). Mean value of SaO2 at day 1 & day 4 was 98.52±1.68 & 94.07±2.36 in group-A (p<0.001) as compared to 97.90±1.99 and 95.40±2.04 in group-B (p<0.001) respectively. Mean pCO2 (mmHg) was 42.32±4.57 & 40.07±3.49 at day 1 & day 4 in group-A (p<0.05) and 40.85±4.03 & 39.61±3.40 in group-B (p>0.05) respectively. Common complications observed were atelectasis (n=29/40; 72.5%), pleural effusion (n=6/40; 15%) and pulmonary edema (n=5/40; 12.5%). Majority (n=19; 47.5%) of patients were discharged till 5th postoperative day. Median stay at hospital was 3 days in group-A & 4 days in group-B and the study concluded that there was an improvement in ABGs and SaO2 after CABG surgery in patients receiving chest physiotherapy interventions. Both techniques are equally effective in preventing and treating chest complications in patients having CABG.
Based on the outcome of the above study in which Group A treated with controlled diaphragmatic breathing as a part of deep breathing exercise along with incentive spirometry had a higher significance when compared to the Group B treated with incentive spirometry alone and thus the alternate hypothesis is accepted and the null hypothesis is rejected.
Conclusion: In conclusion, the present randomized clinical trial provided evidence to support the use of controlled diaphragmatic breathing in the form deep breathing exercise along with incentive spirometry to prevent post operative pulmonary complications by increasing lung volume and capacity, forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) in coronary artery bypass grafting patients compared to use of Incentive spirometry alone. Thus, combination therapy is of great value which can be useful in preventing post operative pulmonary complications following coronary artery bypass grafting.
Keywords: Forced vital capacity (FVC), Forced expiratory volume in one second (FEV1), Incentive Spirometry (IS), controlled Diaphragmatic Breathing (CDB), Relaxed Diaphragmatic Exercises (RDB).
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