Pulmonary complications following cardiac surgery

Interest of thoracic ultrasound after cardiac surgery or interventional cardiology

Thoracic ultrasound has attracted much interest in detecting pleural effusion or pulmonary consolidation after cardiac surgery. In 2016, Trovato reported, in the World Journal of Cardiology, the interest of using, in addition to echocardiography, thoracic ultrasound. In this editorial, we highlight the value of assessing diaphragm function after cardiac surgery and interventional cardiology procedures. Various factors are able to impair diaphragm function after such interventions. Diaphragm motion may be decreased by chest pain secondary to sternotomy, pleural effusion or impaired muscle function. Hemidiaphragmatic paralysis may be secondary to phrenic nerve damage complicating cardiac surgery or atrial fibrillation ablation. Diagnosis may be delayed. Indeed, respiratory troubles induced by diaphragm dysfunction are frequently attributed to pre-existing heart disease or pulmonary complications secondary to surgery. In addition, elevated hemidiaphragm secondary to diaphragm dysfunction is sometimes not observed on chest X-ray performed in supine position in the intensive care unit. Analysis of diaphragm function by ultrasound during the recovery period appears essential. Both hemidiaphragms can be studied by two complementary ultrasound methods. The mobility of each hemidiaphragms is measured by M-mode ultrasonography. In addition, recording the percentage of inspiratory thickening provides important information about the quality of muscle function. These two approaches make it possible to detect hemidiaphragm paralysis or dysfunction. Such a diagnosis is important because persistent diaphragm dysfunction after cardiac surgery has been shown to be associated with adverse respiratory outcome. Early respiratory physiotherapy is able to improve respiratory function through strengthening of the inspiratory muscles i.e. diaphragm and accessory inspiratory muscles.

Application progress of nursing intervention in cardiac surgery

As a stressor, cardiac surgery affects the physiology and psychology of patients, as well as their postoperative recovery. Patients tend to worry about cognitive deficiency, pain, discomfort, the risk of death, sleep, complications, and other factors, resulting in stress and anxiety. Moreover, serious adverse events, such as circulatory and respiratory dysfunction and infection, tend to occur after cardiac surgery and increase the economic burden on patients. Therefore, appropriate nursing interventions should be selected to strengthen patients’ cognitive levels, compliance, and postoperative practices to accelerate their recovery, reduce complications, and shorten hospital stays so as to contribute to patients’ lives and health.

Association of Conventional Ultrafiltration on Postoperative Pulmonary Complications

BACKGROUND

Postoperative pulmonary complications increase mortality after cardiac surgery. Conventional ultrafiltration may reduce pulmonary complications by removing mediators of bypass-induced inflammation and countering hemodilution. We tested the primary hypothesis that conventional ultrafiltration reduces postoperative pulmonary complications, and secondarily, improves early pulmonary function assessed by the ratio of PaO2 to fractional inspired oxygen concentration.

METHODS

This retrospective analysis compared the incidence of postoperative pulmonary complications in adult patients who underwent cardiac surgery, with and without the use of conventional ultrafiltration, by using logistic regression with adjustment for confounding variables. The primary outcome was a composite of reintubation, prolonged ventilation, pneumonia, or pleural effusion. Secondarily, we examined early postoperative lung function using a quantile regression model. We also explored whether red blood cell transfusion differed between groups.

RESULTS

Of 8026 patients, 1043 (13%) received conventional ultrafiltration. After adjustment for confounding variables, the incidence of the composite primary outcome was higher in the conventional ultrafiltration group (12.1% vs 9.9%; P = .03), with an estimated odds ratio of 1.25 (95% CI, 1.02-1.53; P = .03). The median (quantiles) PaO2-to-fractional inspired oxygen concentration ratio was 373 (303-433) vs 368 (303-428), with the estimated adjusted difference in medians of 5 (95% CI, -5.9 to 16; P = .37). The estimated odds ratio of intraoperative transfusion was 1.38 (95% CI, 1.19-1.60; P < .0001) and for postoperative transfusion was 1.30 (95% CI, 1.14-1.49; P = .0001).

CONCLUSIONS

Use of conventional ultrafiltration was not associated with a reduction in the composite of postoperative pulmonary complications or improved early pulmonary function. We found no evidence of benefit from use of conventional ultrafiltration during cardiac surgery.

Comparison of Effects of Liuzijue Exercise and Conventional Respiratory Training on Patients after Cardiac Surgery: A Randomized Controlled Trial

OBJECTIVE

To evaluate the feasibility and safety of Liuzijue exercise (LE) for the clinical effect in patients after cardiac surgery.

METHODS

Totally 120 patients who underwent cardiac surgery and were admitted to the Cardiothoracic Intensive Care Unit of Nanjing Drum Tower Hospital between July and Oclober, 2022 were allocated to the LE group, the conventional respiratory training (CRT) group, and the control group by a random number table at a ratio of 1:1:1; 40 patients in each group. All patients received routine treatment and cardiac rehabilitation. LE group and CRT group respectively performed LE and CRT once a day for 30 min for 7 days. Control group did not receive specialized respiratory training. The forced vital capacity, forced expiratory volume in 1 s, peak inspiratory flow rate, peak expiratory flow rate, maximum inspiratory pressure, maximum expiratory pressure, modified Barthel index (MBI), and Hamilton Rating Scale for Anxiety (HAM-A) were evaluated before, after 3 and 7 days of intervention. In addition, the postoperative length of hospital stay (LOS) and the adverse events that occurred during the intervention period were compared.

RESULTS

A total of 107 patients completed the study, 120 patients were included in the analysis. After 3 days of intervention, the pulmonary function, respiratory muscle strength, MBI and HAM-A of all 3 groups improved compared with that before the intervention (P<0.05 or P<0.01). Compared with the control group, pulmonary function and respiratory muscle strength were significantly improved in the CRT and LE groups (P<0.05 or P<0.01). MBI and HAM-A were significantly improved in the LE group compared with the control and CRT groups (P<0.05 or P<0.01). On the 7th day after intervention, the difference was still statistically significant (P<0.01), and was significantly different from that on the 3rd day (P<0.05 or P<0.01). In addition, on the 7th day of intervention, the pulmonary function and respiratory muscle strength in the LE group were significantly improved compared with those in the CRT group (P<0.01). MBI and HAM-A were significantly improved in the CRT group compared with the control group (P<0.01). There were no significant differences in postoperative LOS among the 3 groups (P>0.05). No training-related adverse events occurred during the intervention period.

CONCLUSIONS

LE is safe and feasible for improving pulmonary function, respiratory muscle strength, the ability to complete activities of daily living and for relieving anxiety of patients after cardiac surgery (Registration No. ChiCTR2200062964).

Success in Supporting Early Mobility and Exercise in a Cardiothoracic Intensive Care Unit

Early mobility contributes to improved patient outcomes and reduced hospital length of stay during acute and intensive care hospitalization. The Bedside Mobility Assessment Tool was implemented in a cardiothoracic intensive care unit during participation in a nationwide evidence-based quality improvement initiative. One outcome included a high level of mobility that was sustained over time. Using the Dynamic Sustainability Framework model, this article describes the key components that contributed to this sustained mobility performance over 4 years.

Effects of early mobilization on pulmonary parameters and complications post coronary artery bypass graft surgery

This study compared the effects of a four-phase and a three-phase early mobilization protocol on respiratory parameters and complications in patients following coronary artery bypass graft surgery. This is a three-arm, parallel-group, randomized controlled clinical trial with 120 candidates for coronary artery bypass graft surgery. Participants were randomly allocated to three groups: four-phase early mobilization protocol, three-phase early mobilization protocol, and control. Arterial blood gases, oxygen saturation, and incidence of pulmonary complications were compared among the groups. Mean arterial blood gases and oxygen saturation improved significantly over time in both four-phase early mobilization protocol and three-phase early mobilization protocol groups compared to control (p < 0.05). There were observed trends for greater improvements in the study outcomes with three-phase early mobilization protocol than four-phase early mobilization protocol; however, did not reach statistically significant levels. The incidence of pulmonary complications was significantly in both intervention groups compared to control (odds ratio: 0.48, 95 % CI 0.007-0.537; p < 0.001). Both four-phase early mobilization and the three-phase early mobilization protocols improved respiratory parameters and reduced pulmonary complications. Statistically insignificant trends were found trends in the three-phase early mobilization protocol, focusing on chest physiotherapy and breathing exercises.

Comparison between dexmedetomidine and propofol on outcomes after coronary artery bypass graft surgery: a retrospective study

Background

Dexmedetomidine (DEX) has a pharmacological profile that should allow rapid recovery and prevent undesirable outcomes such as pulmonary complications.

Methods

This large retrospective study compared the beneficial effects of perioperative infusion of DEX with propofol on the postoperative outcome after coronary artery bypass graft surgery. We reviewed patients’ medical notes at Luoyang Central Hospital from 1st January 2012 to 31st December 2019. All continuous variables, if normally distributed, were presented as mean ± SD; Otherwise, the non-normally distributed data and categorical data were presented as median (25-75 IQR) or number (percentage). The Mann-Whitney U test and Chi-square test were used to evaluate the difference of variables between the DEX and propofol groups. Multivariate logistic regression analysis was performed on the main related and differential factors in the perioperative period.

Results

A total of 1388 patients were included in the study; of those, 557 patients received propofol infusion, and 831 patients received dexmedetomidine. DEX significantly reduced postoperative pulmonary complications compared with propofol, 7.82% vs 13.29%; P < 0.01, respectively. When compared with propofol, DEX significantly shortened the duration of mechanical lung ventilation, 18 (13,25) hours vs 21 (16,37) hours; P < 0.001, the length of stay in the intensive care unit, 51 (42,90) vs 59 (46,94.5) hours; P = 0.001 and hospital stay, 20 (17,24) vs 22 (17,28) days; P < 0.001, respectively. The incidences of postoperative wound dehiscence and infection were significantly reduced with DEX compared with propofol groups, 2.53% vs 6.64%; P < 0.001, respectively. Interestingly, patients receiving DEX had significantly shorter surgical time compared to propofol; 275 (240,310) vs 280 (250,320) minutes respectively (P = 0.005) and less estimated blood loss (P = 0.001).

Conclusion

Perioperative infusion of dexmedetomidine improved the desirable outcomes in patients who had coronary artery bypass graft surgery compared with propofol.

The effect of preoperative chest physiotherapy on oxygenation and lung function in cardiac surgery patients: a randomized controlled study

BACKGROUND

Postoperative pulmonary complications in patients who undergo open heart surgery are serious life-threatening conditions. Few studies have investigated the potentially beneficial effects of preoperative physiotherapy in patients undergoing cardiac surgery.

OBJECTIVES

Assess the effects of preoperative chest physiotherapy on oxygenation and lung function in patients undergoing open heart surgery.

DESIGN

Randomized, controlled.

SETTING

University hospital.

PATIENTS AND METHODS

Patients with planned open heart surgery were randomly allocated into an intervention group of patients who underwent a preoperative home chest physiotherapy program for one week in addition to the traditional postoperative program and a control group who underwent only the traditional postoperative program. Lung function was assessed daily from the day before surgery until the seventh postoperative day.

MAIN OUTCOME MEASURES

Differences in measures of respiratory function and oxygen saturation. Length of postoperative hospital stay was a secondary outcome.

SAMPLE SIZE

100 patients (46 in intervention group, 54 in control group).

RESULTS

Postoperative improvements in lung function and oxygen saturation in the intervention group were statistically significant compared with the control group. The intervention group also had a statistically significant shorter hospital stay (P<.01).

CONCLUSION

Preoperative chest physiotherapy is effective in improving respiratory function following open heart surgery.

LIMITATIONS

Relatively small number of patients.

CONFLICT OF INTEREST

None.

REGISTRATION

ClinicalTrials.gov (NCT04665024).

Multidisciplinary, early mobility approach to enhance functional independence in patients admitted to a cardiothoracic intensive care unit: a quality improvement programme

Early mobilisation following cardiac surgery is vital for improved patient outcomes, as it has a positive effect on a patient's physical and psychological recovery following surgery. We observed that patients admitted to the cardiothoracic intensive care unit (CTICU) following cardiac surgery had only bed exercises and were confined to bed until the chest tubes were removed, which may have delayed patients achieving functional independence. Therefore, the CTICU team implemented a quality improvement (QI) project aimed at the early mobilisation of patients after cardiac surgery.A retrospective analysis was undertaken to define the current mobilisation practices in the CTICU. The multidisciplinary team identified various practice gaps and tested several changes that led to the implementation of a successful early mobility programme. The tests were carried out and reported using rapid cycle changes. A model for improvement methodology was used to run the project. The outcomes of the project were analysed using standard 'run chart rules' to detect changes in outcomes over time and Welch's t-test to assess the significance of these outcomes.This project was implemented in 2015. Patient compliance with early activity and mobilisation gradually reached 95% in 2016 and was sustained over the next 3 years. After the programme was implemented, the mean hours required for initiating out-of-bed-mobilisation was reduced from 22.77 hours to 11.74 hours. Similarly, functional independence measures and intensive care unit mobility scores also showed a statistically significant (p<0.005) improvement in patient transfers out of the CTICU.Implementing an early mobility programme for post-cardiac surgery patients is both safe and feasible. This QI project allowed for early activity and mobilisation, a substantial reduction in the number of hours required for initiating out-of-bed mobilisation following cardiac surgery, and facilitated the achievement of early ambulation and functional milestones in our patients.

Multidisciplinary, early mobility approach to enhance functional independence in patients admitted to a cardiothoracic intensive care unit: a quality improvement programme

Early mobilisation following cardiac surgery is vital for improved patient outcomes, as it has a positive effect on a patient's physical and psychological recovery following surgery. We observed that patients admitted to the cardiothoracic intensive care unit (CTICU) following cardiac surgery had only bed exercises and were confined to bed until the chest tubes were removed, which may have delayed patients achieving functional independence. Therefore, the CTICU team implemented a quality improvement (QI) project aimed at the early mobilisation of patients after cardiac surgery.A retrospective analysis was undertaken to define the current mobilisation practices in the CTICU. The multidisciplinary team identified various practice gaps and tested several changes that led to the implementation of a successful early mobility programme. The tests were carried out and reported using rapid cycle changes. A model for improvement methodology was used to run the project. The outcomes of the project were analysed using standard 'run chart rules' to detect changes in outcomes over time and Welch's t-test to assess the significance of these outcomes.This project was implemented in 2015. Patient compliance with early activity and mobilisation gradually reached 95% in 2016 and was sustained over the next 3 years. After the programme was implemented, the mean hours required for initiating out-of-bed-mobilisation was reduced from 22.77 hours to 11.74 hours. Similarly, functional independence measures and intensive care unit mobility scores also showed a statistically significant (p<0.005) improvement in patient transfers out of the CTICU.Implementing an early mobility programme for post-cardiac surgery patients is both safe and feasible. This QI project allowed for early activity and mobilisation, a substantial reduction in the number of hours required for initiating out-of-bed mobilisation following cardiac surgery, and facilitated the achievement of early ambulation and functional milestones in our patients.

Effect of continuous positive airway pressure associated to exercise on the breathing pattern and heart rate variability of patients undergoing coronary artery bypass grafting surgery: a randomized controlled trial

Continuous positive airway pressure (CPAP) has been used to improve gas exchange and diaphragmatic function, among others benefits. Moreover, it can be used to increase exercise tolerance and positively influence ventilatory function and breathing pattern (BP) during exercise. However, there is no information about the long-term effects of CPAP, as an adjunct to an inpatient cardiac rehabilitation (CR) program, on BP and heart rate variability (HRV) of patients after coronary artery bypass grafting surgery (CABG). Twenty patients were allocated to receive, after randomization, standard inpatient CR without CPAP (control group - CG) or CR with CPAP between 10 to 12 cmH₂O (CPAP group - CPG) associated with the exercises. Participants were assessed preoperatively and on the discharge day, in the sitting rest position. Outcome measurements included BP variables, collected by respiratory inductive plethysmography, and HRV, collected by polar precision performance. The CPG presented lower values of percent rib cage inspiratory and expiratory contributions to tidal volume (%RCi and %RCe) at discharge time, compared to CG. No statistical differences between groups were observed for HRV variables and both groups presented lower values of these indices, compared to preoperative ones. In this context, the patients who received CPAP throughout the whole rehabilitation program were discharged with a better BP, which could indicate more synchronized breathing. CPAP did not influence cardiac autonomic modulation in the long term.

On-Pump Beating Heart versus Off-Pump Coronary Artery Bypass Graft Surgery: Short-Term Follow-up Outcomes of a Single Center

Background and Aim: Novel surgical approaches are gaining attention in an attempt to overcome possible adverse events following coronary artery bypass graft (CABG) surgery. This single-center study aimed to evaluate and compare the early postoperative outcomes of on-pump beating-heart (OPBH-CABG) versus off-pump CABG surgery in similar risk groups with a total number of 1–2 grafts.

Methods: The records of a total of 229 patients who underwent non-emergency, primary, isolated, either OPBH-CABG (n = 32) or off-pump CABG (n = 197) surgery were retrospectively evaluated. Reported outcome measures included baseline data, the number of coronary artery grafts, prophylactic intra-aortic balloon pump, time of extubation from mechanical ventilation, duration of stay in the coronary ICU and hospital, as well as early postoperative complications, in-hospital and early postoperative mortality.

Results: The groups were identical with regards to age and BMI. The patients in the off-pump group received a higher number of grafts (1.84 ± 0.36 vs. 1.18 ± 0.39, p <0.0001). The OPBH-CABG group had a higher Euroscore II score (2.514 ± 1.68 vs. 1.706 ± 1.93, p = 0.021). The time to extubation after the surgery, postoperative length of ICU stay, and total length of hospital stay were similar between the groups (p = 0.2228; p = 0.098; p = 0.717, respectively). The incidence of arrythmia and atrial fibrillation was higher in the on-pump group (12.5% vs. 2.53%, p <0.05). One patient in the on-pump, and four patients in the off-pump groups deceased due to postoperative complications.

Conclusions: OPBH-CABG surgery is comparable to off-pump CABG in terms of early postoperative outcomes. In patients who underwent OPBH-CABG, the risk of arrythmia and atrial fibrillation should be of concern and solved with optimal strategies.