Effects of smoking on pulmonary functions and arterial blood gases following coronary artery surgery in Turkish patients

Impact of smoking on the outcomes of minimally invasive direct coronary artery bypass

BACKGROUND

Tobacco smoking has been associated with an increased risk of complications after conventional coronary surgery. However, the impact of smoking on the risk of postoperative complications in minimally invasive coronary surgery is yet to be studied. We aimed to analyze the impact of the preoperative smoking status on the short- and long-term outcomes of minimally invasive direct coronary artery bypass grafting (MIDCAB) in the context of isolated surgical revascularization or in association with percutaneous coronary intervention.

METHODS

This was a retrospective observational study of all patients undergoing MIDCAB at our institution between 2006 and 2020. Patients were divided into three groups: active smokers, ex-smokers who have quit smoking for at least 1 month before surgery, and non-smokers. The groups were compared using conventional statistical methods. Multivariate analysis was then performed where significant differences were found to eliminate bias.

RESULTS

Throughout the study period, 541 patients underwent MIDCAB, of which 135 (25%) were active smokers, 183 (34%) were ex-smokers, and 223 (41%) were non-smokers. Smokers presented for surgery at a younger age (p < 0.0001), more frequently with a history of myocardial infarction (p < 0.001), peripheral artery disease (p < 0.001) and chronic obstructive pulmonary disease (p < 0.0001). Using multivariate analysis, active smoking was determined to be a significant risk factor for the need of urgent revascularization (odds ratio 2.36 [1.00-5.56], p = 0.049) and the composite of pulmonary complications (including pneumothorax, respiratory infection, respiratory dysfunction, subcutaneous emphysema and exacerbation of chronic obstructive pulmonary disease; odds ratio 2.84 [1.64-4.94], p < 0.001). Preoperative smoking status did not influence the long-term survival (p = 0.83).

CONCLUSIONS

In our study, active smokers presented for MIDCAB at a younger age and more often with signs of atherosclerotic disease (history of myocardial infarction and peripheral artery disease). Active smoking was found to be the most significant risk factor for postoperative pulmonary complications, and is also associated with a more frequent need for urgent surgery at diagnosis. Long-term postoperative survival is not affected by the preoperative smoking status.

Association between smoking and in-hospital mortality in patients with left ventricular dysfunction undergoing coronary artery bypass surgery: a propensity-matched study

Background

Data on the effect of smoking on In-hospital outcome in patients with left ventricular dysfunction undergoing coronary artery bypass graft (CABG) surgery are limited. We sought to determine the influence of smoking on CABG patients with left ventricular dysfunction.

Methods

A retrospective study was conducted using data from the China Heart Failure Surgery Registry database. Eligible patients with left ventricular ejection fraction less than 50% underwent isolated CABGS were included. In addition to the use of multivariate regression models, a 1–1 propensity scores matched analysis was performed. Our study (n = 6531) consisted of 3635 smokers and 2896 non-smokers. Smokers were further divided into ex-smokers (n = 2373) and current smokers (n = 1262).

Results

The overall in-hospital morality was 3.9%. Interestingly, current smokers have lower in-hospital mortality than non-smokers [2.3% vs 4.9%; adjusted odds ratio (OR) 0.612 (95% CI 0.395–0.947) ]. No difference was detected in mortality between ex-smokers and non-smokers [3.6% vs 4.9%; adjusted OR 0.974 (0.715–1.327)]. No significant differences in other clinical end points were observed. Results of propensity-matched analyses were broadly consistent.

Conclusions

It is paradoxically that current smokers had lower in-hospital mortality than non-smokers. Future studies should be performed to further understand the biological mechanisms that may explain this ‘smoker’s paradox’ phenomenon.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02056-9.

Extensive repair of acute type A aortic dissection through a partial upper sternotomy and using complete stent-graft replacement of the arch

BACKGROUND

Partial upper sternotomy (mini-ER) can be used in some adult cardiac surgeries but is seldom performed in the treatment of acute type A aortic dissection (AAAD). This study aimed to assess the feasibility and short-term outcomes of complete stent-graft replacement of the arch with triple-branched stent graft for AAAD through a mini-ER.

METHODS

From 2015 to 2018, 254 patients with AAAD underwent complete stent-graft replacement of the arch with a triple-branched stent graft. Replacement was performed with conventional full sternotomy (con-ER) in 142 patients and with mini-ER in the other 112 patients. Using propensity score matching, the clinical data were compared between 100 patients in the mini-ER group and 100 patients in the con-ER group.

RESULTS

After propensity score matching, there were no significant between-group differences in aortic cross-clamp time, cardiopulmonary bypass time, or total operative time. The amount of mediastinal drainage and number of red blood cell units were significantly lower in the mini-ER group compared with the con-ER group (P < .001). The intubation time was significantly shorter in the mini-ER group (P < .001). The treatment costs were also lower in the mini-ER group (P < .001). There were no significant between-group differences in 30-day mortality (9% vs 8%; P > .99) or postoperative complications.

CONCLUSIONS

This study shows that extensive repair of AAAD through a mini-ER is feasible. It was superior to con-ER in terms of blood loss, postoperative ventilation time, and treatment costs.

Inflammation is related to preoperative hypoxemia in patients with acute Stanford type A aortic dissection

Background

Preoperative hypoxemia is a frequent complication of acute Stanford type A aortic dissection (ATAAD). The aim of the present study was to determine which factors were associated with hypoxemia.

Methods

A series of data were collected in a statistical analysis to evaluate preoperative hypoxemia in patients with ATAAD. After retrospectively analyzing data for 172 patients, we identified the risk factors for preoperative hypoxemia. Hypoxemia was defined by an arterial partial pressure of oxygen to fraction of inspired oxygen (PaO₂/FiO₂) ratio of 200 or lower. Subsequent to identifying the patient population, a prospective study was conducted using ulinastatin as a preoperative intervention. The ulinastatin group received ulinastatin at a total dose of 300,000 units prior to surgery. All the pertinent factors were investigated through univariate and multiple logistic regression analysis.

Results

The factors associated with preoperative hypoxemia in ATAAD comprised the following: body mass index (BMI) ≥25; white blood cell count (WBC) and neutrophil counts; levels of C-reactive protein (CRP), D-dimer, and interleukin-6 (IL-6); ATAAD involving the celiac trunk, renal artery, or mesenteric artery. Logistic regression analysis showed that CRP and IL-6 levels were independent predictive factors. We found that ulinastatin effectively could improve oxygenation, since compared to the control group the oxygenation in the ulinastatin group was significantly improved.

Conclusions

Systemic inflammatory reactions played a vital role in preoperative hypoxemia after the onset of ATAAD. The oxygenation of the patient could be improved significantly by inhibiting the inflammatory response prior to surgery.

Predictors and Outcomes of Sternotomy Conversion and Cardiopulmonary Bypass Assistance in Minimally Invasive Coronary Artery Bypass Grafting

OBJECTIVE

This work's objective was to identify the determinants of conversion of minimally invasive coronary artery bypass grafting to sternotomy, with and without cardiopulmonary bypass assistance, and to compare clinical outcomes in patients who needed conversion.

METHODS

This is a prospectively collected data on patients who underwent minimally invasive coronary bypass done by a single surgeon from February 2005 to September 2014. Statistical analyses were expressed as mean values ± standard deviation or proportions.

RESULTS

The total number of patients was 266, with an average age of 62 years. The median number of grafted territories was 2, higher in those with pump assistance (median, 3 grafts; P ≤ 0.01). Predictors for use of cardiopulmonary bypass included diabetes, 3-vessel disease, left circumflex involvement, and small target vessels (P < 0.05). The rate for sternotomy conversion was 3.8%. Risk factors for conversion to sternotomy included smoking, preoperative bradycardia (<50 beats per minute), low intraoperative ejection fraction, inability to tolerate one-lung ventilation, inadequate surgical exposure, and hemodynamic instability. Postoperative complications included superficial thoracotomy infection (3%), sternotomy infection (10%), new atrial fibrillation (3%), and need for blood transfusion (14%). Twelve patients (5%) developed left-sided pleural effusion that required drainage. There were no perioperative deaths, major adverse cardiac event, or stroke.

CONCLUSIONS

Minimally invasive coronary bypass grafting with conversion to sternotomy and use of cardiopulmonary bypass is safe. Conversions may be alleviated by an effort to optimize modifiable risk factors and the adequacy of surgical exposure. These data may help develop objective selection criteria to identify patients who are excellent candidates for the procedure.

The effect of gender on health-related quality of life and related factors in post-lobectomy lung-cancer patients

PURPOSE

While studies have documented gender differences by histologic type among lung cancer patients, the effect of these differences on the health-related quality of life (HRQoL) of post-lobectomy lungcancer patients and related factors remain uncertain. This study examines gender-specific HRQoL and related factors in post-lobectomy lung-cancer patients.

METHODS

A cross-sectional study design was applied. A convenience sample of 231 post-lobectomy lungcancer patients was recruited from the thoracic surgery outpatient departments of two teaching hospitals in Taipei, Taiwan from March to December 2012. Patients performed a spirometry test and completed instruments that included a Beck Depression Inventory-II, an Interpersonal Support Evaluation List, and the symptom and function scales of the Quality of Life Questionnaire. Data analysis used descriptive statistics, including mean and standard deviations, frequency, and percentage values. Independent-sample Student's t-tests and multivariate analyses were used for comparative purposes.

RESULTS

This study confirmed a significant gender effect on HRQoL and HRQoL-related factors such as marital status, religious affiliation, smoking status, histologic type, symptoms, pulmonary function, depression, and family support. Moreover, multivariate analysis found gender to be a significant determinant of the HRQoL aspects of physical functioning, emotional functioning, and cognitive functioning. Finally, results indicated that factors other than gender were also significant determinants of HRQoL.

CONCLUSION

Gender impacts the HRQoL and related factors of postoperative lung-cancer patients. Therefore, gender should be considered in assessing and addressing the individual care needs of these patients in order to attain optimal treatment outcomes.

Center-level variation in infection rates after coronary artery bypass grafting

BACKGROUND

Health-care-acquired infections (HAIs) are a leading cause of morbidity and mortality after cardiac surgery. Prior work has identified several patient-related risk factors associated with HAIs. We hypothesized that rates of HAIs would differ across institutions, in part attributed to differences in case mix.

METHODS AND RESULTS

We analyzed 20 896 patients undergoing isolated coronary artery bypass grafting surgery at 33 medical centers in Michigan between January 1, 2009, and June 30, 2012. Overall HAIs included pneumonia, sepsis/septicemia, and surgical site infections, including deep sternal wound, thoracotomy, and harvest/cannulation site infections. We excluded patients presenting with endocarditis. Predicted rates of HAIs were estimated using multivariable logistic regression. Overall rate of HAI was 5.1% (1071 of 20 896; isolated pneumonia, 3.1% [n=644]; isolated sepsis/septicemia, 0.5% [n=99]; isolated deep sternal wound infection, 0.5% [n=96]; isolated harvest/cannulation site, 0.5% [n=97]; isolated thoracotomy, 0.02% [n=5]; multiple infections, 0.6% [n=130]). HAI subtypes differed across strata of center-level HAI rates. Although predicted risk of HAI differed in absolute terms by 2.8% across centers (3.9-6.7%; min:max), observed rates varied by 18.2% (0.9-19.1%).

CONCLUSIONS

There was a 18.2% difference in observed HAI rates across medical centers among patients undergoing isolated coronary artery bypass grafting surgery. This variability could not be explained by patient case mix. Future work should focus on the impact of other factors (eg, organizational and systems of clinical care) on risk of HAIs.

Association between Lung Function and Vocal Affections Arising from Tobacco Consumption

Introduction Smoking is a major risk factor for numerous diseases; it is necessary to analyze the impact that the habit can have on vocal health.

Objectives To determine the influence of smoking on changes in vocal production and lung vital capacity compared with nonsmokers.

Methods This cross-sectional study compared smokers and nonsmokers (24 subjects each). Each participant underwent a vocal and spirometric evaluation to measure vital lung capacity.

Results The results showed a worsening in lung vital capacity and other parameters of voice in smokers compared with nonsmokers. Furthermore, the decreased pulmonary vital capacity affected the evaluated voice parameters, and decreased carrying capacity was closely related to smoking. The time and amount of consumption had a direct relationship with the vocal and maximum phonation time.

Conclusions This study showed that smoking causes voice disorders due to lung weakness. Thus, voice changes are affected both directly by interference of smoking on vocal structures and indirectly by increased weakness, which impairs lung vocal production.

Effect of hypercapnia on pleth variability index during stable propofol: Remifentanil anesthesia

BACKGROUND

The pleth variability index (PVI), which is calculated from respiratory variations in the perfusion index (PI), has been shown to predict fluid responsiveness in mechanically ventilated patients; however, vasomotor tone changes induced by hypercapnia can affect PI and hence may slim down the accuracy of PVI. This study was designed to find out the impact of mild hypercapnia on PVI.

METHODS

A total of 30 patients were randomized after induction of general anesthesia with target controlled infusion propofol and remifentanil to either hypercapnia, (etCO2 =45 mmHg), (group 1, 15 patients) or normocapnia (etCO2 =35 mmHg) (group 2, 15 patients). After a stabilization period of 10 min, patients were crossed over to the other intentional level of etCO2. Heart rate (HR), mean arterial pressure (MAP), PI, PVI were collected at the end of each stabilization period.

RESULTS

Patient characteristics and baseline values of HR, MAP, PI and PVI were comparable between the groups. Carryover effect was statistically excluded. Hypercapnia significantly increased PI and decreased PVI with significant negative correlation.

CONCLUSION

Hypercapnia retracts back PVI values compared with normocapnia. Precise judgment of fluid responsiveness as indicated by PVI necessitates its comparison against similar etCO2 levels.

Is there benefit in smoking cessation prior to cardiac surgery?

A best evidence topic was written according to a structured protocol. The question addressed was whether smoking cessation prior to cardiac surgery would result in a greater freedom from postoperative complications. A total of 564 papers were found using the reported searches, of which five represented the best evidence to answer the clinical question. The authors, date, journal, study type, population, main outcome measures and results are tabulated. Reported measures were operative mortality, pulmonary complications, infective complications, neurological complications, transfusion requirements, duration of ventilation, intensive care unit and hospital stay, intensive care unit re-admission, postoperative gas exchange parameters and postoperative pulmonary function. The largest of the best evidence studies demonstrated a significant reduction in pulmonary complications in non-smokers (P < 0.001); however, there was an increased requirement for transfusion in this cohort (P = 0.002). There were non-significant reductions in neurological complications, infective complications and re-admissions to intensive care. Another large cohort study demonstrated significant reductions in non-smokers in mortality (P < 0.0001), pulmonary complications (P = 0.0002), infection (P < 0.0007), intensive care unit re-admission (P = 0.0002), duration of mechanical ventilation (P = 0.026) and intensive care unit stay (P = 0.002). A larger cohort study again demonstrated significant reductions in non-smokers in pulmonary complications (P < 0.002), duration of mechanical ventilation (P < 0.012) and intensive care unit stay (P < 0.005). A smaller prospective cohort study reported significantly raised PaO(2) (P = 0.0091) and reduced PaCO(2) (P < 0.0001) levels in the non-smokers as well as improved FVC and FEV(1) (P < 0.0001). There were also reductions in duration of intubation (P < 0.0001), intensive care unit stay (P < 0.0001) and hospital stay (P < 0.0013). Another small cohort study reporting outcomes of heart transplantation demonstrated significant improvement in non-smokers in terms of survival (P = 0.031), duration of intubation (P = 0.05) and intensive care unit stay (P = 0.021). We conclude that there is strong evidence demonstrating superior outcomes in non-smokers following cardiac surgery and advocate the necessity of smoking cessation as soon as possible prior to cardiac surgery.

Assessment of pulmonary function tests in cardiac patients

This study was aimed to assess the pulmonary function tests (PFTs) in cardiac patients; with ischemic or rheumatic heart diseases as well as in patients who underwent coronary artery bypass graft (CABG) or valvular procedures. For the forty eligible participants, the pulmonary function was measured using the spirometry test before and after the cardiac surgery. Data collection sheet was used for the patient's demographic and intra-operative information. Cardiac diseases and surgeries had restrictive negative impact on PFTs. Before surgery, vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), ratio between FEV1 and FVC, and maximum voluntary ventilation (MVV) recorded lower values for rheumatic patients than ischemic patients (P values were 0.01, 0.005, 0.0001, 0.031, and 0.035, respectively). Moreover, patients who underwent valvular surgery had lower PFTs than patients who underwent CABG with significant differences for VC, FVC, FEV1, and MVV tests (P values were 0.043, 0.011, 0.040, and 0.020, respectively). No definite causative factor appeared to be responsible for those results although mechanical deficiency and incisional chest pain caused by cardiac surgery are doubtful. More comprehensive investigation is required to resolve the case.

Postoperative study of vital capacity and ventilation measurements following elective craniotomy

CONTEXT AND OBJECTIVE

Changes in pulmonary function commonly occur after general surgery. The aims were to evaluate vital capacity, tidal volume and respiratory frequency among patients undergoing elective craniotomy and to determine possible correlations of these parameters with surgery duration and etiology for neurosurgery.

DESIGN AND SETTING

Prospective, open study at a tertiary university hospital.

METHODS

Twenty-six patients underwent elective craniotomy for aneurysm clipping (11) or tumor resection (15). Vital capacity (VC), tidal volume (TV), minute volume (VE) and respiratory rate were determined before the operation and on the first to fourth postoperative days.

RESULTS

There were significant decreases of 25% in VC, 22% in TV and 12% in VE (p < 0.05) and no significant increase in respiratory frequency (5%) on the first postoperative day. VE returned to baseline on the second postoperative day and TV on the third postoperative day, while VC was 8% lower on the fourth postoperative day, compared with before the operation (p < 0.05). VC reduction was significantly greater in patients undergoing aneurysm clipping (43%) than in patients undergoing tumor resection (14%) when surgery duration was more than four hours (p < 0.05), with no significant change when surgery duration was less than four hours.

CONCLUSION

Reductions in VC, TV and VE were observed during the postoperative period in patients undergoing aneurysm clipping or tumor resection. The reductions in VC and TV were greater in patients undergoing craniotomy due to aneurysm and with longer surgery duration.

A donor history of smoking affects early but not late outcome in lung transplantation

BACKGROUND

Liberalization of tobacco exposure history as an exclusion to lung donation has recently occurred to increase donor organ availability. This study investigated the effect of donor smoking status and current and cumulative cigarette dose on early and late outcomes in lung transplantation.

METHODS

From 1995 to 2002, 173 heart-lung and bilateral single-lung transplant recipients were retrospectively reviewed. Seventy-seven (45%) of 173 donors were ever-smokers and 64 of those 77 were current smokers. These were divided into subgroups by current number of cigarettes smoked to investigate acute dose effects and by pack-year to investigate cumulative dose effects. Risks of smoking were assessed by univariate and multivariate hazard regression models.

RESULTS

Univariate analysis revealed that there were significant differences between current and cumulative dose subgroups in early postoperative variables, including Pao2/Fio2 ratio, ventilation time, and intensive care unit stay. Additionally, these variables were dose dependent. There was no significant difference in 3-year survival between never-smokers and ever-smokers (73% versus 64%, P = 0.27), and a rate of decline of survival was similar. There was a trend for the percentage of patients dying of bronchiolitis obliterans syndrome to be lower in the ever-smokers group compared with the never-smokers group (6% versus 11%, respectively). Multivariate analysis revealed current and cumulative smoking as a risk factor for early but not late outcomes.

CONCLUSIONS

Donor smoking history had a significant effect on early outcomes in lung transplantation in a current and cumulative dose-dependent fashion. However, no significant effect on late outcomes, including bronchiolitis obliterans syndrome, was seen.