Forced expiratory volume in one second predicts length of stay and in-hospital mortality in patients undergoing cardiac surgery: a retrospective cohort study

Liposomal bupivacaine intercostal block placed under direct vision reduces morphine use in thoracic surgery

Background

Thoracic epidural analgesia (TEA) and liposomal bupivacaine (LB) are two methods used for postoperative pain control after thoracic surgery. Some studies have compared LB to standard bupivacaine. However, data comparing the outcomes of LB to TEA after minimally invasive lung resection is limited. Therefore, the objective of our study was to compare postoperative pain, opioid usage, and outcomes between patients who received TEA vs. LB.

Methods

We conducted a retrospective chart review of patients who underwent minimally invasive lung resections over an 8-month period. Intraoperatively, patients received either LB under direct vision or a TEA. Pain scores were obtained in the post-anesthesia care unit (PACU) and at 12, 24, and 48 hours postoperatively. Morphine milligram equivalents (MMEs) were calculated at 24 and 48 hours postoperatively. Postoperative outcomes were then compared between groups.

Results

In total, 391 patients underwent minimally invasive lung resection: 236 (60%) wedge resections, 51 (13%) segmentectomies, and 104 (27%) lobectomies. Of these, 326 (83%) received LB intraoperatively. Fewer patients in the LB group experienced postoperative complications (18% vs. 34%, P=0.004). LB patients also had lower median pain scores at 24 (P=0.03) and 48 hours (P=0.001) postoperatively. There was no difference in MMEs at 24 hours (P=0.49). However, at 48 hours, patients who received LB required less narcotics (P=0.02). Median hospital length of stay (LOS) was significantly shorter in patients who received LB (2 vs. 4 days, P<0.001). On multivariable analysis, increasing age, postoperative complications, and use of TEA were independently associated with a longer hospital LOS.

Conclusions

Compared to TEA, LB intercostal block placed under direct vision reduced morphine use 48 hours after thoracic surgery. It was also associated with fewer postoperative complications and shorter median hospital LOS. LB is a good alternative to TEA for pain management after minimally invasive lung resection.

Association between hospital-acquired functional decline and 2-year readmission or mortality after cardiac surgery in older patients: a multicenter, prospective cohort study

BACKGROUND

Hospital-acquired functional decline (HAFD) is a new predictor of poor prognosis in hospitalized older patients.

AIMS

We aimed to assess the impact of HAFD on the prognosis of older cardiac surgical patients 2 years after discharge.

METHODS

This multicenter prospective cohort study assessed 293 patients with cardiac disease aged ≥ 65 years who underwent cardiac surgery at 7 Japanese hospitals between June 2017 and June 2018. The primary endpoint was the composite outcome of cardiovascular-related readmission and all-cause mortality 2 years after discharge. HAFD was assessed using the total Short Physical Performance Battery at hospital discharge.

RESULTS

The primary outcome was observed in 17.3% of the 254 included patients, and HAFD was significantly associated with the primary outcome. Female sex (hazard ratio [HR], 2.451; 95% confidence interval [CI] 1.232-4.878; P = 0.011), hemoglobin level (HR, 0.839; 95% CI 0.705-0.997; P = 0.046), preoperative frailty (HR, 2.391; 95% CI 1.029-5.556; P = 0.043), and HAFD (HR, 2.589; 95% CI 1.122-5.976; P = 0.026) were independently associated with the primary outcome. The incidence rate of HAFD was 22%, with female sex (odds ratio [OR], 1.912; 95% CI 1.049-3.485; P = 0.034), chronic obstructive pulmonary disease (OR, 3.958; 95% CI 1.413-11.086; P = 0.009), and the time interval (days) between surgery and the start of ambulation (OR, 1.260, 95% CI 1.057-1.502; P = 0.010) identified as significant factors.

DISCUSSION

HAFD was found to be an independent prognostic determinant of the primary outcome 2 years after discharge.

CONCLUSION

HAFD prevention should be prioritized in the hospital care of older cardiac surgery patients.

Pulmonary Function Tests for the Prediction of Postoperative Pulmonary Complications

BACKGROUND

Pulmonary function tests (PFTs) such as spirometry and blood gas analysis have been claimed to improve preoperative risk assessment. This systematic review summarizes the available scientific literature regarding the ability of PFTs to predict postoperative pulmonary complications (PPC) in non-thoracic surgery.

METHODS

We systematically searched MEDLINE, CINAHL, and the Cochrane Library for pertinent original research articles (PROSPERO CRD42020215502), framed by the PIT-criteria (PIT, participants, index test, target conditions), respecting the PRISMA-DTA recommendations (DTA, diagnostic test accuracy).

RESULTS

46 original research studies were identified that used PFT-findings as index tests and PPC as target condition. QUADAS-2 quality assessment revealed a high risk of bias regarding patient selection, blinding, and outcome definitions. Qualitative synthesis of prospective studies revealed inconclusive study findings: 65% argue for and 35% against preoperative spirometry, and 43% argue for blood gas analysis. A (post-hoc) subgroup analysis in prospective studies with low-risk of selection bias identified a possible benefit in upper abdominal surgery (three studies with 959 participants argued for and one study with 60 participants against spirometry).

CONCLUSION

As the existing literature is inconclusive it is currently unknown if PFTs improve risk assessment before non-thoracic surgery. Spirometry should be considered in individuals with key indicators for chronic obstructive pulmonary disease (COPD) scheduling for upper abdominal surgery.

Hospital-Acquired Functional Decline and Clinical Outcomes in Older Cardiac Surgical Patients: A Multicenter Prospective Cohort Study

This study aimed to determine the effect of hospital-acquired functional decline (HAFD) on prognosis, 1-year post-hospital discharge, of older patients who had undergone cardiac surgery in seven Japanese hospitals between June 2017 and June 2018. This multicenter prospective cohort study involved 247 patients with cardiac disease aged ≥65 years. HAFD was defined as a decrease in the short physical performance battery at hospital discharge compared with before surgery. Primary outcomes included a composite outcome of frailty severity, total mortality, and cardiovascular readmission 1-year post-hospital discharge. Secondary outcomes were changes in the total score and sub-item scores in the Ki-hon Checklist (KCL), assessed pre- and 1-year postoperatively. Poor prognostic outcomes were observed in 33% of patients, and multivariate analysis identified HAFD (odds ratio [OR] 3.43, 95% confidence interval [CI] 1.75–6.72, p < 0.001) and low preoperative gait speed (OR 2.47, 95% CI 1.18–5.17, p = 0.016) as independent predictors of poor prognosis. Patients with HAFD had significantly worse total KCL scores and subscale scores for instrumental activities of daily living, mobility, oral function, and depression at 1-year post-hospital discharge. HAFD is a powerful predictor of prognosis in older patients who have undergone cardiac surgery.

Influence of reduced diffusing capacity and FEV1 on outcome after cardiac surgery

BACKGROUND

Impaired lung function is a well-known risk factor in cardiac surgery patients and reduced forced expiratory volume in 1 second (FEV₁ ) is associated with increased mortality. However, there is limited knowledge regarding the influence of impaired diffusing capacity of the lungs for carbon monoxide (DLCO) in unselected cardiac surgery patients. The aim of this study was to investigate the association of impaired DLCO and/or reduced FEV₁ on post-operative mortality and morbidity in cardiac surgery patients.

METHODS

In a prospective cohort study, 390 patients scheduled for elective cardiac surgery underwent preoperative lung function test including spirometry and DLCO measurements. We defined reduced FEV₁ as FEV₁ below lower limit of normal (LLN) and impaired DLCO as DLCO <60% of predicted.

RESULTS

Mortality within 1 year (90-570 days) was significantly higher in patients with impaired DLCO (12% vs 3%, P = .010) and with reduced FEV₁ (9% vs 3%, P = .028). Mortality was higher in patients with impaired DLCO both in the presence and absence of FEV₁  < LLN. In multivariate analysis, only impaired DLCO [OR: 3.3, 95% confidence interval (CI) 1.4-7.5; P = .005] and age (OR: 1.1 per year, 95% CI 1.0-1.2; P = .001) were independent predictors of the combined outcome of mortality and prolonged intensive care unit (ICU) stay. Impaired DLCO was also associated with post-operative respiratory complications.

CONCLUSION

In patients undergoing elective cardiac surgery, preoperative impaired FEV₁ and DLCO were associated with increased mortality and morbidity. In multivariate analysis, only DLCO and age were independent predictors of a combined outcome of mortality and prolonged ICU stay.

The predictive value of preimplant pulmonary function testing in LVAD patients

BACKGROUND

The predictive value of preoperative pulmonary function testing (PFT) in left ventricular assist device (LVAD) patients remains unknown. This study evaluates the relationship between abnormal PFTs and postimplant outcomes in LVAD patients.

METHODS

LVAD implants from January 2004 to December 2018 at a single institution were included. Patients were stratified based on the presence of abnormal preoperative PFTs, and the primary outcome was respiratory adverse events (AE). Secondary outcomes included 1-year overall postimplant survival, and complications including bleeding, renal failure, thromboembolism, and device malfunction.

RESULTS

The total of 333 patients underwent LVAD implant, 46.5% (n = 155) with normal PFTs and 53.5% (n = 178) with abnormal PFTs. Patients with abnormal PFTs were noted to have higher rates of respiratory AEs (25.9% vs. 15.1%, p = .049). In multivariable analysis, the impact of PFTs was most significant when forced expiratory volume in 1 s/forced expiratory volume (FEV1/FVC) ratio was less than 0.5 (hazard ratio [HR] 16.32, 95% confidence interval [CI], 1.70-156.78). The rates of other AEs including bleeding, renal failure, right heart failure, and device malfunction were similar. One-year overall postimplant survival was comparable between the groups (56.8% vs. 68.8%, p = .3183), though patients in the lowest strata of FEV1 (<60% predicted) and FEV1/FVC (<0.5) had elevated risk-adjusted hazards for mortality (HR 2.63, 95% CI, 1.51-4.60 and HR 18.92, 95% CI, 2.10-170.40, respectively).

CONCLUSIONS

The presence of abnormal preoperative PFTs is not prohibitory for LVAD implantation although it can be used for risk stratification for respiratory AEs and mortality, particularly in patients with severely reduced metrics. The importance of careful patient selection should be underscored in this higher risk patient subset.

Spirometry Assessment and Correlation With Postoperative Pulmonary Complications in Cardiac Surgery Patients

Objective

To observe spirometry and its correlation with postoperative pulmonary complications in cardiac surgery patients.

Study design

Prospective observational study

Place and duration of the study

Chaudhary Pervaiz Elahi Institute of Cardiology (CPEIC) Multan, from January 1, 2017, to June 30, 2020

Methodology

Written informed consent was taken from 357 patients. Spirometry was performed in all the patients using the conventional method. Baseline data, including gender, age, body mass index (BMI), living area, smoking history, known lung illness, six-minute walk distance, predicted forced vital capacity (FVC) %, predicted forced expiratory volume in one second (FEV1) %, and type of the procedure such as aortic valve replacement (AVR), coronary artery bypass grafting (CABG), double-valve replacement (DVR), and mitral valve replacement (MVR) were documented for all the patients. Outcome data included postoperative ICU length of stay (LOS), respiratory failure, respiratory infection, atelectasis, and mortality.

Results

The most common procedure was CABG and MVR proceeded by n=254 (71.1%) and n=83 (23.2%) patients, respectively. Postoperative complications, such as respiratory failure, respiratory infection, and atelectasis, was noted in n=29 (8.1%), n=28 (7.8 %), and n=127 (35.6 %) patients, respectively, while n=5 (1.4%) patients died.

Conclusion

Deranged pulmonary function tests (PFTs) are associated with poor prognosis following elective cardiac surgery in terms of postoperative pulmonary complications such as pulmonary infection, respiratory failure, and atelectasis. There is a significant difference in percentage predicted of FVC and FEV1 in patients who developed atelectasis and respiratory tract infection.

Early extubation in current valve surgery requiring long cardiopulmonary bypass: Benefits and predictive value of preoperative spirometry

BACKGROUND

Early extubation (EEx) after cardiac surgery has been essentially studied in patients with short cardiopulmonary bypass (CPB). Whether preoperative spirometry can predict EEx remains controversial.

OBJECTIVES

To investigate whether EEx can be a goal and predicted by preoperative spirometry in valve surgery requiring long CPB.

METHODS

Nonemergent consecutive 210 patients who underwent valve surgery from January 2014 to August 2019 were investigated retrospectively.

RESULTS

EEx (<8 h) was achieved in 93 (44.3%) patients without increasing adverse events. Patients with EEx had shorter ICU and hospital stays than those without EEx. Multivariate analysis showed that higher estimated glomerular filtration rate and mitral valve repair were significant protective factors for EEx. Conversely, moderate and severe chronic obstructive pulmonary disease defined by spirometry, longer operation, CPB, and aortic cross-clamp time were significant risk factors.

CONCLUSIONS

EEx should be the goal in current valve surgery. Preoperative spirometry is a significant predictor.

Postoperative Delirium in Patients with Chronic Obstructive Pulmonary Disease after Coronary Artery Bypass Grafting

Background and Objectives: The incidence of postoperative delirium (POD) in patients with chronic obstructive pulmonary disease (COPD) is unclear. It seems that postoperative respiratory problems that may occur in COPD patients, including prolonged mechanical ventilation or respiratory-tract infections, may contribute to the development of delirium. The aim of the study was to identify a relationship between COPD and the occurrence of delirium after cardiac surgery and the impact of these combined disorders on postoperative mortality. Materials and Methods: We performed an analysis of data collected from 4151 patients undergoing isolated coronary artery bypass grafting (CABG) in a tertiary cardiac-surgery center between 2012 and 2018. We included patients with a clinical diagnosis of COPD according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria. The primary endpoint was postoperative delirium; Confusion Assessment Method in the Intensive Care Unit (CAM-ICU) was used for delirium assessment. Results: Final analysis included 283 patients with COPD, out of which 65 (22.97%) were diagnosed with POD. Delirious COPD patients had longer intubation time (p = 0.007), more often required reintubation (p = 0.019), had significantly higher levels of C-reactive protein (CRP) three days after surgery (p = 0.009) and were more often diagnosed with pneumonia (p < 0.001). The CRP rise on day three correlated positively with the occurrence of postoperative pneumonia (r = 0.335, p = 0.005). The probability of survival after CABG was significantly lower in COPD patients with delirium (p < 0.001). Conclusions: The results of this study confirmed the relationship between chronic obstructive pulmonary disease and the incidence of delirium after cardiac surgery. The probability of survival in COPD patients undergoing CABG who developed postoperative delirium was significantly decreased.

Association of preoperative spirometry with cardiopulmonary fitness and postoperative outcomes in surgical patients: A multicentre prospective cohort study

BACKGROUND

Preoperative spirometry and cardiopulmonary exercise testing (CPET) may stratify risk for respiratory complications. This secondary analysis of the Measurement of Exercise Tolerance before Surgery (METS) study examined whether CPET performance (i.e., cardiopulmonary fitness) confounds associations of spirometry with outcomes.

METHODS

The analysis included 1200 participants having major non-cardiac surgery at 25 hospitals in Canada, Australia, New Zealand and UK. Forced expiratory volume in 1 s (FEV₁), and ratio of FEV₁ to forced vital capacity (FVC) were measured during preoperative spirometry, and peak oxygen consumption and ventilatory efficiency during preoperative CPET. Outcomes were respiratory morbidity (Postoperative Morbidity Survey) and pulmonary complications (pneumonia or respiratory failure). We used multivariable logistic regression models to estimate associations of FEV₁ with outcomes after adjustment for risk factors and either peak oxygen consumption or ventilatory efficiency.

FINDINGS

128 participants (11%) developed respiratory morbidity, and 48 (4%) developed pulmonary complications. There was no strong evidence that FEV₁ predicted respiratory morbidity after adjustment for peak oxygen consumption (p = 0·80) or ventilatory efficiency (p = 0·76), or FEV₁ predicted pulmonary complications after adjustment for ventilatory efficiency (p = 0·37). Peak oxygen consumption (odds ratio 0·66 per 5 mL/kg/min increase; 95% CI, 0·54-0·82) was associated with respiratory morbidity. Ventilatory efficiency was associated with respiratory morbidity (p = 0·04) and pulmonary complications (p = 0·02). Peak oxygen consumption also confounded the association between FEV₁ and respiratory morbidity.

INTERPRETATION

After accounting for fitness and clinical factors, FEV₁ was not strongly predictive of respiratory complications. Prior associations between FEV₁ and respiratory morbidity may be explained by confounding by peak oxygen consumption.

FUNDING

Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Ontario Ministry of Health and Long-Term Care, Ontario Ministry of Research, Innovation and Science, UK National Institute of Academic Anaesthesia, UK Clinical Research Collaboration, Australian and New Zealand College of Anaesthetists, and Monash University.

Abnormal pulmonary function tests are associated with prolonged ventilation and risk of complications following elective cardiac surgery

Elective cardiac surgery accounts for a significant proportion of perioperative resource allocation in Australasia. Preoperative pulmonary function testing (PFT) is routinely undertaken in some centres to identify patients who may require prolonged ventilation and intensive care unit (ICU) stay, although there are currently no data supporting this practice. Routine PFT places a burden on respiratory diagnostic laboratories, is inconvenient to patients and may delay surgery. We aimed to identify whether PFT parameters identify patients requiring prolonged mechanical ventilation after elective cardiac surgery. Adult patients admitted to the Royal Adelaide Hospital ICU following elective cardiac surgery between July 2013 and December 2017 were identified retrospectively from the local ICU database. Preoperative PFT and operative and postoperative outcome data were retrieved from local databases, and multivariable logistic regression was undertaken to identify which PFT variables were associated with prolonged mechanical ventilation. PFT data were available for 835/1139 (73%) elective cardiac surgical cases. The best independent predictors of prolonged mechanical ventilation were post-bronchodilator forced vital capacity (FVC) and single-breath diffusing capacity for carbon monoxide (DLCO). Patients with FVC <80% predicted and DLCO <60% predicted had an odds ratio for prolonged postoperative ventilation of 7.5 (95% confidence intervals 3.6–15.6; P < 0.001). The area under the receiver operating characteristic curve derived from this model was 0.68. Abnormal PFT results were associated with prolonged postoperative mechanical ventilation. A PFT-based prediction tool does not accurately predict individual patient outcome but identifies a cohort of patients at higher risk of requiring prolonged ventilation, potentially informing ICU resource allocation and surgical planning.

Preoperative pulmonary function in all comers for cardiac surgery predicts mortality†

OBJECTIVES

Although reduced lung function and chronic obstructive pulmonary disease (COPD) is associated with higher risk of death following cardiac surgery, preoperative spirometry is not performed routinely. The aim of this study was to investigate the relationship between preoperative lung function and postoperative complications in all comers for cardiac surgery irrespective of smoking or COPD history.

METHODS

Preoperative spirometry was performed in elective adult cardiac surgery patients. Airflow obstruction was defined as the ratio of forced expiratory volume in 1 s (FEV1)/forced vital capacity ratio below the lower limit of normal (LLN) and reduced forced ventilatory capacity defined as FEV1 <LLN.

RESULTS

A history of COPD was reported by 132 (19%) patients; however, only 74 (56%) had spirometry-verified airflow obstruction. Conversely, 64 (12%) of the 551 patients not reporting a history of COPD had spirometry-verified airflow obstruction. The probability of death was significantly higher in patients with airflow obstruction (8.8% vs 4.5%, P = 0.04) and in patients with a FEV1 <LLN (8.7% vs 3.7%, P = 0.007). In the multivariate analysis were age [hazard ratio (HR) 1.6, 95% confidence interval (CI) 1.0-2.5; P = 0.04], prolonged cardiopulmonary bypass time (HR 1.2, 95% CI 1.02-1.3; P = 0.03), reduced kidney function (HR 2.5, 95% CI 1.2-5.6; P = 0.02) and FEV1 <LLN (HR 2.4, 95% CI 1.1-5.2; P = 0.03) all independently associated with an increased risk of death.

CONCLUSIONS

Preoperative spirometry reclassified 18% of the patients. A reduced FEV1 independently doubled the risk of death. Inclusion of preoperative spirometry in routine screening of cardiac surgical patients may improve risk prediction and identify high-risk patients.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01614951 (ClinicalTrials.gov).

Lung function and outcomes in emergency medical admissions

BACKGROUND

We examine the ability of pre-existing measures of Forced Expiratory Volume in 1 s (FEV1), and Diffusion Capacity for Carbon Monoxide (DLCO) to determine the subsequent 30-day mortality outcome following unselected acute medical admission.

METHODS

Between 2002 and 2017, we studied all emergency medical admissions (106,586 episodes in 54,928 patients) of whom 8071 were classified as respiratory. We employed logisitic multiple variable regression models to evaluate the ability of FEV1 or DLCO to predict the 30-day hospital mortality outcome.

RESULTS

The 30-day hospital episode mortality outcome demonstrated curvilinear relationships to the underlying FEV1 or DLCO values; adjusted for major outcome predictors, a higher FEV1 - OR 0.85 (95% CI: 0.82, 0.89) or DLCO OR 0.76 (95% CI: 0.73, 0.79) values predicted survival. The range of predicted mortalities was from 3.3% (95% CI: 2.5, 4.0) to 23.5% (95% CI: 20.8, 26.2); the FEV1 (Model1) and DLCO (Model2) outcome prediction was essentially equivalent (Chi2 = 2.9: p = 0.08).

CONCLUSION

The 30-day mortality outcome was clearly related to the pre-admission FEV1 and DLCO value. The outcome relationship was curvilinear. Either parameter appears a useful tool to explore hospital outcomes. Previously suggested cut-points are likely an artefact and not supported by these data.

A multicenter study to evaluate pulmonary function in osteogenesis imperfecta

Pulmonary complications are a significant cause for morbidity and mortality in osteogenesis imperfecta (OI). However, to date, there have been few studies that have systematically evaluated pulmonary function in individuals with OI. We analyzed spirometry measurements, including forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1 ), in a large cohort of individuals with OI (n = 217) enrolled in a multicenter, observational study. We show that individuals with the more severe form of the disease, OI type III, have significantly reduced FVC and FEV1 which do not follow the expected trends of the normal population. We also show that "normalization" of FVC and FEV1 using general population data to generate percent predicted values underestimates the pulmonary involvement in OI. Within each subtype of OI, we used linear mixed models to find potential correlations between FEV1 and FVC with the clinical variables including mobility, bisphosphonate use, and scoliosis. Our results are an important step in understanding the extent of pulmonary involvement in individuals with OI and for developing pulmonary endpoints for use in the routine patient care as well as in the investigation of new therapies.

The Efficacy of Inpatient vs. Home-Based Physiotherapy Following Coronary Artery Bypass Grafting

Background: Intensive post-operative physiotherapy after cardiac surgery helps to reduce the number of complications, accelerating convalescence and decreasing peri-operative mortality. Cardiac rehabilitation is aimed at regaining lost function and sustaining the effect of cardiac surgery. The aim of this study was to compare the efficacy of inpatient and home-based phase II physiotherapy following coronary artery bypass grafting, and inpatient phase II post-operative physiotherapy based on the analysis of the spirometry results. Methods: A prospective observational study included 104 adult patients of both sexes undergoing planned coronary artery bypass grafting and were randomized to one of the two groups-inpatients (InPhysio) and home-based (HomePhysio) at a 1:1 ratio. All patients had undergone spirometry testing prior to surgery (S1) and on the fifth day after the operation (S2), i.e., on the day of completion of the first phase (PI) of physiotherapy. Both the study group (InPhysio) and the control group (HomePhysio) performed the same set of exercises in the second phase (PII) of cardiac physiotherapy, either in the hospital or at home, respectively, according to the program obtained in the hospital. Both groups have undergone spirometry testing (S3) at 30 days after the operation. Results: The demographic and peri-operative data for both groups were comparable and showed no statistically significant differences. An analysis of gradients between the results of spirometry tests before surgery and at 30 days after the surgery showed a smaller decrease in forced vital capacity (FVC) in the study group than in the control group (p < 0.001). The results at five and 30 days after the surgery showed a greater increase in FVC in the study group than in the control group (680 mL vs. 450 mL, p = 0.009). There were no statistically significant differences in other parameters studied. Conclusions: The advantage of inpatient over home-based physiotherapy was evidenced by much smaller decreases in FVC between the initial and final tests, and greater increases between the fifth day after surgery and the final test. Our analysis showed greater efficacy of inpatient physiotherapy as compared with home-based exercises and raises concerns about patient adherence.

The effect of high-flow nasal oxygen on hospital length of stay in cardiac surgical patients at high risk for respiratory complications: a randomised controlled trial

There has been increased interest in the prophylactic and therapeutic use of high‐flow nasal oxygen in patients with, or at risk of, non‐hypercapnic respiratory failure. There are no randomised trials examining the efficacy of high‐flow nasal oxygen in high‐risk cardiac surgical patients. We sought to determine whether routine administration of high‐flow nasal oxygen, compared with standard oxygen therapy, leads to reduced hospital length of stay after cardiac surgery in patients with pre‐existing respiratory disease at high risk for postoperative pulmonary complications. Adult patients with pre‐existing respiratory disease undergoing elective cardiac surgery were randomly allocated to receive high‐flow nasal oxygen (n = 51) or standard oxygen therapy (n = 49). The primary outcome was hospital length of stay and all analyses were carried out on an intention‐to‐treat basis. Median (IQR [range]) hospital length of stay was 7 (6–9 [4–30]) days in the high‐flow nasal oxygen group and 9 (7–16 [4–120]) days in the standard oxygen group (p=0.012). Geometric mean hospital length of stay was 29% lower in the high‐flow nasal group (95%CI 11–44%, p = 0.004). High‐flow nasal oxygen was also associated with fewer intensive care unit re‐admissions (1/49 vs. 7/45; p = 0.026). When compared with standard care, prophylactic postoperative high‐flow nasal oxygen reduced hospital length of stay and intensive care unit re‐admission. This is the first randomised controlled trial examining the effect of prophylactic high‐flow nasal oxygen use on patient‐centred outcomes in cardiac surgical patients at high risk for postoperative respiratory complications.

The Relationship between Diabetes Mellitus and Respiratory Function in Patients Eligible for Coronary Artery Bypass Grafting

Introduction: Spirometry performed prior to surgery provides information on the types of lung disorders in patients. The purpose of this study was to look for a relationship between the prevalence of diabetes and spirometry parameters. Material and Methods: The study was conducted in patients with coronary artery disease who were eligible for an isolated coronary artery bypass graft in 2013. The study group included 367 patients (287 men and 80 women) aged 68.7 ± 8.4 years. They were divided into those with diagnosed diabetes (group I, n = 138, 37.6%) and without diabetes (group II, n = 229, 62.4%). Spirometry tests were performed on the day of admission to the hospital. Results: Patients with diabetes (group I) had a significantly higher body mass index than those without diabetes (group II). Spirometry tests also showed that patients with diabetes had statistically significantly lower forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1.0). Both FVC and FEV1.0 were also statistically significantly lower for overweight and obese individuals in group I than those in group II. Conclusion: Patients with diabetes eligible for coronary artery bypass grafting with concurrent overweight or obesity are more likely to have lower spirometry parameters than those without diabetes.

Analysis of the influence of respiratory disorders observed in preoperative spirometry on the dynamics of early inflammatory response in patients undergoing isolated coronary artery bypass grafting

Background

Preoperative spirometry provides measurable information about the occurrence of respiratory disorders. The aim of this study was to assess the association between preoperative spirometry abnormalities and the intensification of early inflammatory responses in patients following coronary artery bypass graft in extracorporeal circulation.

Material and methods

The study involved 810 patients (625 men and 185 women) aged 65.4±7.9 years who were awaiting isolated coronary artery bypass surgery. On the basis of spirometry performed on the day of admittance to the hospital, the patients were divided into three groups. Patients without respiratory problems constituted 78.8% of the entire group. Restricted breathing was revealed by spirometry in 14.9% and obstructive breathing in 6.3% of patients.

Results

Inter-group analysis showed statistically significant differences in C-reactive protein (CRP) between patients with restrictive spirometry abnormalities and patients without any pulmonary dysfunction. CRP concentrations differed before surgery (P=0.006) and on the second (P<0.001), fourth (P=0.005) and sixth days after surgery (P=0.029). There was a negative correlation between CRP levels and FEV₁.

Conclusion

In our study, the most common pulmonary disorders in the coronary artery bypass graft patients were restrictive. Patients with abnormal spirometry results from restrictive respiratory disorders have an elevated level of generalized inflammatory response both before and after the isolated coronary artery bypass surgery. Therefore, this group of patients should be given special postoperative monitoring and, in particular, intensive respiratory rehabilitation immediately after reconstitution.

Prevalence and Implications of Abnormal Respiratory Patterns in Cardiac Surgery: A Prospective Cohort Study

OBJECTIVE

To investigate the prevalence and impact of abnormal respiratory patterns in cardiac surgery patients.

DESIGN

Prospective cohort study.

SETTING

Tertiary hospital.

PARTICIPANTS

Patients scheduled for elective coronary artery bypass graft surgery.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Pulmonary function tests were performed in 454 patients before surgery. Abnormal respiratory patterns were defined as follows: obstructive (forced expiratory volume in 1 s [FEV₁]/forced vital capacity [FVC]<0.70), restrictive (FEV₁/FVC≥0.70 and FVC<80% of predicted), and mixed (FEV₁/FVC<0.70 and both FEV₁ and FVC<80% of predicted). Of the 31 patients with a history of chronic obstructive pulmonary disease, no abnormal respiratory pattern was confirmed in 5. Of the 423 patients without a history of lung disease, the authors newly identified 57 obstructive, 46 restrictive, and 4 mixed patterns. Therefore, lung disease was reclassified in 24.7% of cases. Independent predictors of obstructive pattern were age, male sex, history of smoking, and chronic obstructive pulmonary disease. Obstructive lung disease was associated with 16 hours or longer ventilation. A reduced FEV₁ was associated with a likelihood of atrial fibrillation (1-L decrement, odds ratio: 1.38, 95% confidence interval: 1.01-to-1.90, p = 0.04) and hospitalization time (regression coefficient: 1.23, 95% confidence interval: 0.54-to-1.91, p<0.001).

CONCLUSIONS

Abnormal respiratory patterns are common and often underdiagnosed in the cardiac surgery setting. Pulmonary function tests help reveal patients at risk of complications and may provide an opportunity for intervention.

Ten Years Experiences With Preoperative Evaluation Clinic for Day Admission Cardiac and Major Vascular Surgical Patients: Model for "Perioperative Anesthesia and Surgical Home"

Admission on the day of surgery for elective cardiac and noncardiac surgery is the prevalent practice in North America and Canada. This approach realizes medical, psychological and logistical benefits, and its success is predicated on an effective outpatient preoperative evaluation. The establishment of a highly functional preoperative clinic with a comprehensive set up and efficient logistical pathways is invaluable. This notion in recent years has included the entire perioperative period, and the concept of a perioperative anesthesia/surgical home (PASH) is gaining popularity. The anesthesiologists as perioperative physicians can organize and lead the entire process from the preoperative evaluation, through the hosptial discharge. The functions of the PASH include preoperative optimization of medical conditions and psychological preparation of the patients and their support system; the care in the operating room and intensive care unit; pain management; respiratory therapy; cardiac rehabilitation; and specialized nutrition. Along with oversight of the medical issues, the preoperative visit is an opportune time for counseling, clarification of expectations and discussion of research, as well as for utilization of various informatics systems to consolidate the pertinent information and distribute it to relevant health care providers. We review the scientific foundation and practical applications of a preoperative visit and share our experience with the development of the preoperative evaluation clinic, designed specifically for cardiac and major vascular patients scheduled for day admission surgery. The ultimate goal of preoperative evaluation clinic is to ensure a safe, efficient, and cost-effective perioperative care for patients undergoing a complex type of surgery.

The association of chronic lung disease with early mortality and respiratory adverse events after aortic valve replacement

BACKGROUND

We studied the association between components of chronic lung disease (CLD) assessment and operative outcomes in patients undergoing aortic valve replacement (AVR) for aortic stenosis.

METHODS

From 2011 to 2012, 9,177 patients included in The Society of Thoracic Surgeons (STS) Cardiac Surgery Database underwent AVR for aortic stenosis with complete pulmonary function tests (PFT) and CLD data (31% of AVRs). We evaluated markers of CLD and their association with operative mortality, pulmonary morbidity, and length of hospital stay using multivariable logistic regression analysis.

RESULTS

In a selected population of AVR patients with PFTs, CLD was prevalent in 50% (mild, 25.6%; moderate, 13.2%; severe, 11.2%). Predicted forced expiratory volume in 1 second (FEV1) was obtained in all patients and diffusion capacity of the lung for carbon monoxide (DLCO), arterial oxygen tension (PaO2), and arterial carbon dioxide tension (PaCO2) in 31%. The STS predicted risk of operative mortality, mortality, pulmonary morbidity, and hospital stay increased with severity of CLD and with low FEV1, DLCO, and PaO2. Moderate and severe CLD were independently associated with operative mortality (odds ratio [OR] 2.88, 95% confidence interval [CI]: 2.0-4.5), pulmonary morbidity (OR 2.33, 95% CI: 1.93-2.8), and prolonged hospital stay (OR 2.73, 95% CI: 2.17-3.45). Low FEV1 was independently associated with pulmonary morbidity and prolonged hospital stay. Low PaO2 and DLCO were independently associated with a combined mortality and pulmonary morbidity endpoint.

CONCLUSIONS

CLD is associated with adverse operative outcomes in selected patients with aortic stenosis undergoing AVR. FEV1, DLCO, and PaO2 may add important information to current risk adjustment models beyond the broad CLD classification.