Perioperative Care in Cardiac Surgery: A Joint Consensus Statement by the Enhanced Recovery After Surgery (ERAS) Cardiac Society, ERAS International Society, and The Society of Thoracic Surgeons (STS)

Enhanced Recovery After Surgery (ERAS) programs have been shown to lessen surgical insult, promote recovery, and improve postoperative clinical outcomes across a number of specialty operations. A core tenet of ERAS involves the provision of protocolized evidence-based perioperative interventions. Given both the growing enthusiasm for applying ERAS principles to cardiac surgery and the broad scope of relevant interventions, an international, multidisciplinary expert panel was assembled to derive a list of potential program elements, review the literature, and provide a statement regarding clinical practice for each topic area. This article summarizes those consensus statements and their accompanying evidence. These results provide the foundation for best practice for the management of the adult patient undergoing cardiac surgery.

Tau and Aβ42 in lavage fluid of pneumonia patients are associated with end-organ dysfunction: A prospective exploratory study

BACKGROUND

Bacterial pneumonia and sepsis are both common causes of end-organ dysfunction, especially in immunocompromised and critically ill patients. Pre-clinical data demonstrate that bacterial pneumonia and sepsis elicit the production of cytotoxic tau and amyloids from pulmonary endothelial cells, which cause lung and brain injury in naïve animal subjects, independent of the primary infection. The contribution of infection-elicited cytotoxic tau and amyloids to end-organ dysfunction has not been examined in the clinical setting. We hypothesized that cytotoxic tau and amyloids are present in the bronchoalveolar lavage fluid of critically ill patients with bacterial pneumonia and that these tau/amyloids are associated with end-organ dysfunction.

METHODS

Bacterial culture-positive and culture-negative mechanically ventilated patients were recruited into a prospective, exploratory observational study. Levels of tau and Aβ42 in, and cytotoxicity of, the bronchoalveolar lavage fluid were measured. Cytotoxic tau and amyloid concentrations were examined in comparison with patient clinical characteristics, including measures of end-organ dysfunction.

RESULTS

Tau and Aβ42 were increased in culture-positive patients (n = 49) compared to culture-negative patients (n = 50), independent of the causative bacterial organism. The mean age of patients was 52.1 ± 16.72 years old in the culture-positive group and 52.78 ± 18.18 years old in the culture-negative group. Males comprised 65.3% of the culture-positive group and 56% of the culture-negative group. Caucasian culture-positive patients had increased tau, boiled tau, and Aβ42 compared to both Caucasian and minority culture-negative patients. The increase in cytotoxins was most evident in males of all ages, and their presence was associated with end-organ dysfunction.

CONCLUSIONS

Bacterial infection promotes the generation of cytotoxic tau and Aβ42 within the lung, and these cytotoxins contribute to end-organ dysfunction among critically ill patients. This work illuminates an unappreciated mechanism of injury in critical illness.

Efficacy of ultrasound-guided erector spinae plane block on analgesia and quality of recovery after minimally invasive direct coronary artery bypass surgery: protocol for a randomized controlled trial

BACKGROUND

Minimally invasive direct coronary artery bypass (MIDCAB) surgery offers an effective option for coronary artery disease (CAD) patients with the avoidance of median sternotomy and fast postoperative recovery. However, MIDCAB is still associated with significant postoperative pain which may lead to delayed recovery. The erector spinae plane block (ESPB) is a superficial fascial plane block. There have not been randomized controlled trials evaluating the effects of ESPB on analgesia and patient recovery following MIDCAB surgery. We therefore designed a double-blind prospective randomized placebo-controlled trial, aiming to prove the hypothesis that ESPB reduces postoperative pain scores in patients undergoing MIDCAB surgery.

METHODS

The study protocol has been reviewed and approved by the Ethical Review Committee of Peking University People's Hospital. Sixty adult patients of either sex scheduled for MIDCAB surgery under general anesthesia (GA) will be included. Patients will be randomly allocated to receive either a preoperative single-shot ESPB with 30 mL of ropivacaine 0.5% (ESPB group) or normal saline 0.9% (control group). The primary outcomes are the difference between the two groups in numeric rating scale (NRS) scores at rest at different time points (6, 12, 18, 24, 48 h) after surgery. The secondary outcomes include NRS scores on deep inspiration within 48 h, postoperative hydromorphone consumption, and quality of patient recovery at 24 h and 48 h, using the Quality of Recovery-15 (QoR-15) scale. The other outcomes include intraoperative fentanyl requirements, the need for additional postoperative rescue analgesics, time to tracheal extubation and chest tube removal after surgery, incidence of postoperative nausea and vomiting (PONV) and postoperative cognitive dysfunction (POCD), intensive care unit (ICU) length of stay (LOS), hospital discharge time, and 30-day mortality. Adverse events will be also evaluated.

DISCUSSION

This is a novel randomized controlled study evaluating a preoperative ultrasound-guided single-shot unilateral ESPB on analgesia and quality of patient recovery in MIDCAB surgery. The results of this study will characterize the degree of acute postoperative pain and clinical outcomes following MIDCAB. Our study may help optimizing analgesia regimen selection and improving patient comfort in this specific population.

TRIAL REGISTRATION

The study was prospectively registered with the Chinese Clinical Trial Registry (trial identifier: ChiCTR2100052810). Date of registration: November 5, 2021.

Ultrasound-guided erector spinae plane block for postoperative analgesia in patients undergoing minimally invasive direct coronary artery bypass surgery: a double-blinded randomized controlled trial

PURPOSE

Minimally invasive direct coronary artery bypass (MIDCAB) surgery is associated with significant postoperative pain. We aimed to investigate the efficacy of ultrasound-guided erector spinae plane block (ESPB) for analgesia after MIDCAB.

METHODS

We conducted randomized controlled trial in 60 patients undergoing MIDCAB who received either a single-shot ESPB with 30 mL of ropivacaine 0.5% (ESPB group, n = 30) or normal saline 0.9% (control group, n = 30). The primary outcome was numerical rating scale (NRS) pain scores at rest within 48 hr postoperatively. The secondary outcomes included postoperative NRS pain scores on deep inspiration within 48 hr, hydromorphone consumption, and quality of recovery-15 (QoR-15) score at 24 and 48 hr.

RESULTS

Compared with the control group, the ESPB group had lower NRS pain scores at rest at 6 hr (estimated mean difference, -2.1; 99% confidence interval [CI], -2.7 to -1.5; P < 0.001), 12 hr (-1.9; 99% CI, -2.6 to -1.2; P < 0.001), and 18 hr (-1.2; 99% CI, -1.8 to -0.6; P < 0.001) after surgery. The ESPB group also showed lower pain scores on deep inspiration at 6 hr (-2.9; 99% CI, -3.6 to -2.1; P < 0.001), 12 hr (-2.3; 99% CI, -3.1 to -1.5; P < 0.001), and 18 hr (-1.0; 99% CI, -1.8 to -0.2; P = 0.01) postoperatively. Patients in the ESPB group had lower total intraoperative fentanyl use, lower 24-hr hydromorphone consumption, a shorter time to extubation, and a shorter time to intensive care unit (ICU) discharge.

CONCLUSION

Erector spinae plane block provided early effective postoperative analgesia and reduced opioid consumption, time to extubation, and ICU discharge in patients undergoing MIDCAB.

TRIAL REGISTRATION

www.chictr.org.cn (ChiCTR2100052810); registered 5 November 2021.

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.

Impact of Post-Operative Infection after CABG on Long-Term Survival

Coronary artery bypass grafting (CABG) is one of the most common cardiac surgical procedures. It is commonly known that post-operative infection has a negative impact on the patient's short-term treatment outcomes and long-term prognosis. The aim of the present study was to assess the impact of perioperative infection on 5-year and 10-year survival in patients undergoing elective on-pump CABG surgery. The present prospective observational study was carried out between 1 July 2010 and 31 August 2012 among patients undergoing cardiac surgery at our centre. Infections were identified according to the ECDC definitions. We initially assessed the incidence of infection and its relationship with the parameters analysed. We then analysed the effect of particular parameters, including infection, on 5-year and 10-year survival after surgery. We also analysed the impact of particular types of infection on the risk of death within the period analysed. The significant risk factors for reduced survival were age (HR 1.05, CI 1.02-1.07), peripheral artery disease (HR 1.99, CI 1.28-3.10), reduced LVEF after surgery (HR 0.96, CI 0.94-0.99), post-operative myocardial infarction (HR 1.45, CI 1.05-2.02) and infection (HR 3.10, CI 2.20-4.28). We found a strong relationship between post-operative infections and 5-year and 10-year mortality in patients undergoing CABG. Pneumonia and BSI were the only types of infection that were found to have a significant impact on increased long-term mortality after CABG surgery.

Effect of Ventilation Strategy During Cardiopulmonary Bypass on Arterial Oxygenation and Postoperative Pulmonary Complications After Pediatric Cardiac Surgery: A Randomized Controlled Study

OBJECTIVES

To compare the effects of 3 ventilation strategies during cardiopulmonary bypass (CPB) on arterial oxygenation and postoperative pulmonary complications (PPCs).

DESIGN

A prospective, randomized, controlled study.

SETTING

A single-center tertiary teaching hospital.

PARTICIPANTS

One hundred twenty pediatric patients undergoing elective repair of congenital acyanotic heart diseases with CPB.

INTERVENTIONS

Patients were assigned randomly into 3 groups according to ventilation strategy during CPB as follows: (1) no mechanical ventilation (NOV), (2) continuous positive airway pressure (CPAP) of 5 cmH₂O, (3) low tidal volume (LTV), pressure controlled ventilation (PCV), respiratory rate (RR) 20-to-30/min, and peak inspiratory pressure adjusted to keep tidal volume (Vt) 2 mL/kg.

MEASUREMENTS AND MAIN RESULTS

The PaO₂/fraction of inspired oxygen (F_IO₂) ratio and PaO₂ were higher in the 5 minutes postbypass period in the LTV group but were nonsignificant. The PaO₂/F_IO₂ ratio and PaO₂ were significant after chest closure and 1 hour after arrival to the intensive care unit with a higher PaO₂/F_IO₂ ratio and PaO₂ in the LTV group. Regarding the oxygenation index, the LTV group was superior to the NOV group at the 3 time points, with lower values in the LTV group. There were no significant differences in the predictive indices among the 3 groups, including the extubation time, and postoperative intensive care unit stays days. The incidence of PPCs did not significantly differ among the 3 groups.

CONCLUSIONS

Maintaining ventilation during CPB was associated with better oxygenation and did not reduce the incidence of PPCs in pediatric patients undergoing cardiac surgery.

Nosocomial Extracardiac Infections After Cardiac Surgery

Purpose of Review

Nosocomial extracardiac infections after cardiac surgery are a major public health issue affecting 3–8.2% of patients within 30–60 days following the intervention.

Recent Findings

Here, we have considered the most important postoperative infective complications that, in order of frequency, are pneumonia, surgical site infection, urinary tract infection, and bloodstream infection. The overall picture that emerges shows that they cause a greater perioperative morbidity and mortality with a longer hospitalization time and excess costs. Preventive interventions and corrective measures, diminishing the burden of nosocomial extracardiac infections, may reduce the global costs. A multidisciplinary team may assure a more appropriate management of nosocomial extracardiac infections leading to a reduction of hospitalization time and mortality rate.

Summary

The main and most current data on epidemiology, prevention, microbiology, diagnosis, and management for each one of the most important postoperative infective complications are reported. The establishment of an antimicrobial stewardship in each hospital seems to be, at the moment, the more valid strategy to counteract the challenging problems.

Association Between Early Speech-Language Pathology Consultation and Pneumonia After Cardiac Surgery

PURPOSE

Patients undergoing cardiac surgery are reported to be at higher risk for oropharyngeal dysphagia and aspiration, which may predispose them to respiratory complications such as pneumonia. Speech-language pathology consultation facilitates early identification of swallowing difficulties providing appropriate and timely interventions during the postoperative period. This study explores the association between pneumonia and timing of speech-language pathology order entry and evaluation following cardiac surgery.

METHOD

A retrospective study was performed on adults who underwent cardiac surgery in a tertiary care center, from July 2016 through December 2019. Patients with preexisting tracheostomy upon admission for cardiac surgery were excluded. The medical records of patients who had speech-language pathology consultation orders for swallowing concerns were analyzed in order to compare the timing of speech-language pathology order entry, completion of speech-language pathology evaluation, and incidence of pneumonia during hospitalization following cardiac surgery.

RESULTS

During the study period, 3,168 patients underwent cardiac surgery, of which 2,864 patients met the inclusion criteria. Speech-language pathology was ordered for 473 cases (16.5%), and clinical swallow evaluation (CSE) was completed by speech-language pathology in 419 patients (88.6%), of which 309 patients were suspected to have dysphagia (73.7%). Among the 2,391 patients without speech-language pathology consultation, pneumonia was reported in 34 patients (1.42%). Pneumonia was reported in 53 patients in the speech-language pathology cohort, of which 43 patients (13.9%) were suspected to have dysphagia. Patients with pneumonia had significantly longer median time (20.0 hr, range: 4.9-26.7) from speech-language pathology orders to completion of CSE, compared to those without pneumonia (13.2 hr, range: 3.2-22.4, p = .025). There was no significant difference in the median time from extubation to speech-language pathology consultation order time in patients with pneumonia versus those without pneumonia. Patients with pneumonia were observed to have prolonged, although not statistically significant, median time from extubation to CSE (70.4 hr, range: 21.2-215) compared to those without pneumonia (42.2 hr, range: 19.5-105.8, p = .066).

CONCLUSIONS

Patients without pneumonia in the postoperative period were observed to have shorter median time from extubation to speech-language pathology evaluation. Future studies are needed to further understand the impact of early speech-language pathology consultation and incidence of pneumonia in this population.

The Use of Corticosteroids for Cardiopulmonary Bypass in Adults

Purpose of Review

Cardiopulmonary bypass for on-pump cardiac surgery induces a systemic inflammation that may contribute to postoperative major complications. To reduce this inflammatory response in patients undergoing heart surgery, the perioperative use of anti-inflammatory corticosteroids has long been recommended to improve clinical outcomes. However, the efficacy and safety of steroids remain still unclear.

Recent Findings

We reviewed recent published literature, including the large clinical trials DECS and SIRS and the two meta-analysis by Dvirnik et al. (2018) and Ng et al. (2020), on mortality and major postoperative complications, such as myocardial complications, atrial fibrillation, stroke, pulmonary adverse events, length of ICU and hospital stay, renal failure, and infection.

Summary

The perioperative application of corticosteroids did not improve mortality rates beyond standard care or other secondary outcomes, such as myocardial infarction, stroke, renal failure, and infection. The observed increased risk of myocardial damage in patients receiving corticosteroids in the SIRS trial is mainly related to the author-defined CK-MB threshold as indicator for early myocardial injury. Interestingly, the use of steroids may have some beneficial effects on secondary outcomes: they significantly decreased the risk of respiratory failure and pneumonia and shortened the length of ICU and hospital stay, but the mechanism involved in pulmonary injury is multifactorial and it is difficult to evaluate this result. Patients receiving steroids did not have a decreased incidence of atrial fibrillation shown by the two large trials unlike some previous small sample size trials have demonstrated.

Associations of creatinine/cystatin C ratio and postoperative pulmonary complications in elderly patients undergoing off-pump coronary artery bypass surgery: a retrospective study

Sarcopenia along with nutritional status are associated with postoperative pulmonary complications in various surgical fields. Recently, the creatinine/cystatin C ratio and CONtrolling NUTritional status score were introduced as biochemical indicators for sarcopenia and malnutrition, respectively. We aimed to investigate the associations among these indicators and postoperative pulmonary complications in elderly patients undergoing off-pump coronary artery bypass surgery. We reviewed the medical records of 605 elderly patients (aged ≥ 65 years) who underwent off-pump coronary artery bypass surgery from January 2010 to December 2019. Postoperative pulmonary complications (pneumonia, prolonged ventilation [> 24 h], and reintubation during post-surgical hospitalisation) occurred in 80 patients. A 10-unit increase of creatinine/cystatin C ratio was associated with a reduced risk of postoperative pulmonary complications (odds ratio: 0.80, 95% confidence interval: 0.69–0.92, P = 0.001); the optimal cut-off values for predicting postoperative pulmonary complications was 89.5. Multivariable logistic regression analysis revealed that age, congestive heart failure, and creatinine/cystatin C ratio < 89.5 (odds ratio 2.36, 95% confidence interval 1.28–4.37) were independently associated with the occurrence of postoperative pulmonary complications, whereas CONtrolling NUTritional status score was not. A low creatinine/cystatin C ratio was associated with an increased risk of developing postoperative pulmonary complications after off-pump coronary artery bypass surgery.

Impact of postoperative complications after cardiac surgery on long-term survival

PURPOSE

The impact of postoperative complications on long-term survival is not well characterized. We sought to study the prevalence of postoperative complications after cardiac surgery and their impact on long-term survival.

METHODS

Operative survivors (n = 26,221) who underwent coronary artery bypass grafting (CABG) (n = 13,054, 49.8%), valve surgery (n = 8667, 33.1%) or combined CABG and valve surgery (n = 4500, 17.2%) from 1993 to 2019 were included in the study. Records were reviewed for postoperative complications and long-term survival. Propensity-match analysis was performed between patients who did and did not have a postoperative complication. The associations between postoperative complications and survival were assessed using a Cox-proportional model.

RESULTS

Complications occurred in 17,463 (66.6%) of 26,221 operative survivors. A total of 17 postoperative complications were analyzed. Postoperative blood product use was the commonest (n = 12,397, 47.3%), followed by atrial fibrillation (n = 8399, 32.0%), prolonged ventilation (n = 2336, 8.9%), renal failure (n = 870, 3.3%), reoperation for bleeding (n = 859, 3.3%) and pacemaker/ICD insertion (n = 795, 3.0%). Stroke (hazard ratio [HR]: 1.55; 95% confidence interval [CI]: 1.36-1.77), renal failure (HR: 1.45; 95% CI: 1.33-1.58) and pneumonia (HR: 1.23; 95% CI: 1.11-1.36) had the strongest impact on long-term survival. Long-term survival decreased as the number of postoperative complications increased.

CONCLUSIONS

Postoperative complications after cardiac surgery significantly impact outcomes that extend beyond the postoperative period. Stroke, renal failure, and pneumonia are particularly associated with poor long-term survival.

Diaphragm Dysfunction After Cardiac Surgery: Reappraisal

OBJECTIVES

The aim of this study was to re-investigate the incidence, risk factors, and outcomes of postoperative diaphragmatic dysfunction (DD) with actual cardiac surgery procedures.

DESIGN

Single-center, retrospective, observational study based on a prospectively collected database.

SETTING

Tertiary care cardiac surgery center.

PARTICIPANTS

Patients who underwent cardiac surgery between January 2016 and September 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The DD group included patients with clinically perceptible diaphragmatic paralysis, which was confirmed by chest ultrasound (amplitude of the diaphragm movement in time-motion mode at rest, after a sniff test). The primary endpoint was the incidence of DD. Among 3,577 patients included, the authors found 272 cases of DD (7.6%). Individuals with DD had more arterial hypertension (64.3% v 52.6%; p < 0.0001), higher body mass index (BMI) (28 [25-30] kg/m²v 26 [24-29] kg/m²; p < 0.0002), and higher incidence of coronary bypass grafting (CABG) (58.8% v 46.6%; p = 0.0001). DD was associated with more postoperative pneumonia (23.9% v 8.7%; p < 0.0001), reintubation (8.8% v 2.9%; p < 0.0001), tracheotomy (3.3% v 0.3%; p < 0.0001), noninvasive ventilation (45.6% v 5.4%; p < 0.0001), duration of mechanical ventilation (five [four-11] hours v four [three-six] hours; p < 0.0001), and intensive care unit and hospital stays (14 [11-17] days v 13 [11-16] days; p < 0.0001). In multivariate analysis, DD was associated with CABG (odds ratio [OR] 1.9 [1.5-2.6]; p = 0.0001), arterial hypertension (OR 1.4 [1.1-1.9]; p = 0.008), and BMI (OR per point 1.04 [1.01-1.07] kg/m²; p = 0.003).

CONCLUSIONS

The incidence of symptomatic DD after cardiac surgery was 7.6%, leading to respiratory complications and increased ICU stay. CABG was the principal factor associated with DD.

The modified water swallowing test score is the best predictor of postoperative pneumonia following extubation in cardiovascular surgery: A retrospective cohort study

No guidelines have been established for the evaluation of swallowing function following extubation. The factors of bedside swallowing evaluations (BSEs) that are associated with the development of pneumonia have not been fully elucidated. This study aimed to retrospectively investigate the most appropriate measurements of BSEs for predicting pneumonia.The study subjects were 97 adults who underwent BSEs following cardiovascular surgery. Patients were divided into the pneumonia onset group (n = 21) and the non-onset group (n = 76). Patient characteristics, intraoperative characteristics, complications, BSE results, and postoperative progress were compared between the groups. BSEs were composed of consciousness level, modified water swallowing test (MWST) score, repetitive saliva swallowing test score, speech intelligibility score, and risk of dysphagia in the cardiac surgery score. Univariate and multivariate analyses with the BSE as the independent variable and pneumonia onset as the dependent variable were also performed to identify factors that predict pneumonia. For factors that became significant in univariate analysis, the incidence of pneumonia was shown using the Kaplan-Meier curve.No significant differences were found in patient characteristics, intraoperative characteristics, and complications between the 2 groups. The postoperative progress was significantly different between the 2 groups, the pneumonia-onset group had a significantly longer time until the start of oral intake and a significantly lower median value of Food Intake Level Scale at the time of discharge. According to univariate and multivariate analyses, MWST score was a significant factor for predicting the onset of pneumonia even after adjusting for patient characteristics and surgical factors, and the incidence of pneumonia increased approximately 3 times when the MWST score was 3 points or less.The MWST score after extubation in cardiovascular surgery was the strongest predictor of postoperative pneumonia in BSEs. Furthermore, the incidence of pneumonia increased approximately 3 times when the MWST score was 3 points or less. Predicting cases with a high risk of developing pneumonia allows nurses and attending physicians to monitor the progress carefully and take aggressive preventive measures.

Microbial Contamination after Cardiac Surgery in a Hospital Cardiac Surgery Ward

Surgery site infection is one of the most common postoperative complications which is associated with increased morbidity, mortality and admission costs. It is considered a priority to determine the level of nosocomial infection and its control in reflecting the quality of care. Therefore, this study aimed to evaluate the microbial contamination after cardiac surgery at a hospital cardiac surgery ward of Besat Hospital, Tehran.

In this cross-sectional descriptive-analytic study (2013-2017), 610 patients underwent surgery at the Department of Cardiac Surgery of Besat Hospital. All necessary information such as urine culture, surgical site, histopathologic examination for the diagnosis of microbial contamination and microorganisms were collected from the patient records and inserted in the questionnaire. The data were analyzed using SPSS (version 25).

The incidence of nosocomial infections following cardiac surgery reportedly ranged from 17% to 23%. Accordingly, pneumonia (51.2%) and local infections (22%) were the most common infections in the studied population. The mortality rate in our population was 11.4%. Moreover, 64.3% of the total mortality cases were reported in patients with sepsis. The mean age and duration of admission of patients with catheter infection were significantly higher than other subjects.

Given the relatively high prevalence of the infection and its importance, it is necessary to take more serious measures to prevent and control these infections.

Impact of nosocomial infections on patient mortality following cardiac surgery

STUDY OBJECTIVE

To determine the rate of nosocomial infection among patients undergoing cardiac surgery and to identify risk factors and the impact of these infections on patient mortality.

DESIGN

Prospective observational study.

SETTING

Intensive Care Unit (ICU).

PATIENTS

1097 adult patients who underwent cardiac surgery at Hospital Clínico Universitario de Valladolid between January 2011 and January 2016.

INTERVENTIONS

None.

MEASUREMENTS

Preoperative, intraoperative and postoperative medical, surgical and anaesthetic variables.

MAIN RESULTS

A total of 111 patients (10.1%) acquired a nosocomial infection in the postoperative period. Pneumonia was the most frequent (4.2%) nosocomial infection. Three independent risk factors for the development of a nosocomial infection were identified: cardiopulmonary bypass time, kidney failure and emergency surgery. The stay in the ICU was significantly higher in patients who developed a nosocomial infection (16.6 ± 38.8 vs. 4.4 ± 17.8, P < 0.001). The mortality rate of patients who acquired a nosocomial infection was significantly greater (18%) than that of patients who did not acquire a nosocomial infection (5%) (P < 0.001). The 90-day survival was greater in the group of patients without nosocomial infection (log rank 27.55, P < 0.001). The dynamic modelling of 90-day mortality revealed that in the first week, cardiopulmonary bypass time (HR = 1.00, 95% CI 1.00-1.02, P < 0.001) and emergency surgery (HR = 0.12, 95% CI 0.04-0.37, P < 0.001) were the most important risk factors for mortality, while after the first week, nosocomial infection (HR = 6.23, 95% CI 2.49-15.63, P < 0.001) was the main risk factor, followed by cardiopulmonary bypass time (HR = 1.01, 95% CI 1.00-1.01, P = 0.001) and EuroSCORE (HR = 1.03, 95% CI 1.00-1.06, P = 0.008).

CONCLUSIONS

Nosocomial infections after cardiac surgery constitute the main independent risk factor for mortality after the first week of surgery. These data suggest that its prevention following cardiac surgery must be prioritised to improve patient outcomes.

Low Tidal Volume Mechanical Ventilation Against No Ventilation During Cardiopulmonary Bypass in Heart Surgery (MECANO): A Randomized Controlled Trial

BACKGROUND

Postoperative pulmonary complications are common after cardiac surgery and have been related to lung collapse during cardiopulmonary bypass (CPB). No consensus exists regarding the effects of maintaining mechanical ventilation during CPB to decrease these complications.

RESEARCH QUESTION

To determine whether maintaining low-tidal ventilation (3 mL/kg 5 times/min, with positive end expiratory pressure of 5 cm H₂O) during CPB (ventilation strategy) was superior to a resting-lung strategy with no ventilation (no ventilation strategy) regarding postoperative pulmonary complications, including mortality.

STUDY DESIGN AND METHODS

In a randomized controlled trial, patients undergoing cardiac surgery at a single center from May 2017 through August 2019 were randomized to the ventilation or no ventilation strategy during CPB (1:1 ratio). Apart from the CPB phase, perioperative ventilation procedures were standardized.

RESULTS

The study included 1,501 patients (mean age, 68.8 ± 10.3 years; 1,152 (76.7%) men; mean EuroSCORE II, 2.3 ± 2.7). Seven hundred fifty-six patients were in the ventilation strategy group, and no differences existed in baseline characteristics and types of procedures between the two groups. An intention-to-treat analysis yielded no significant difference between the ventilation and no ventilation groups regarding incidence of the primary composite outcome combining death, early respiratory failure, ventilation support beyond day 2, and reintubation, with 112 of 756 patients (14.8%) in the ventilation group vs 133 of 745 patients (17.9%) in the no ventilation group (OR, 0.80; 95% CI, 0.61-1.05; P = .11). Strict per-protocol analyses of 1,338 patients (89.1%) with equally distributed preoperative characteristics yielded similar results (OR, 0.81; 95% CI, 0.60-1.09; P = .16). Post hoc analysis of the subgroup who underwent isolated coronary artery bypass graft procedures (n = 725) showed that the ventilation strategy was superior to the no ventilation strategy regarding the primary outcome (OR, 0.56; 95% CI, 0.37-0.84; P = .005).

INTERPRETATION

Among patients undergoing cardiac surgery with CPB, continuation of low tidal volume ventilation was not superior to no ventilation during CPB with respect to postoperative complications, including death, early respiratory failure, ventilation support beyond day 2, and reintubation.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT03098524; URL: www.clinicaltrials.gov.

Cystatin C regulates the cytotoxicity of infection-induced endothelial-derived β-amyloid

Infection of rat pulmonary microvascular endothelial cells with the bacterium Pseudomonas aeruginosa induces the production and release of cytotoxic oligomeric tau and beta amyloid (Aβ). Here, we characterized these cytotoxic amyloids. Cytotoxic behavior and oligomeric tau were partially resistant to digestion with proteinase K, but cytotoxicity was abolished by various denaturants including phenol, diethylpyrocarbonate (DEPC), and 1,1,1,3,3,3-hexafluoro-2-isopropanol (HFIP). Ultracentrifugation for 8 h at 150 000 g was required to remove cytotoxic activity from the supernatant. Ultracentrifugation, DEPC treatment, and immunodepletion using antibodies against Aβ also demonstrated that cytoprotective protein(s) are released from endothelial cells during P. aeruginosa infection. Mass spectrometry of endothelial cell culture media following P. aeruginosa infection allowed identification of multiple potential secreted modulators of Aβ, including cystatin C, gelsolin, and ApoJ/clusterin. Immunodepletion, co-immunoprecipitation, and ultracentrifugation determined that the cytoprotective factor released during infection of endothelial cells by P. aeruginosa is cystatin C, which appears to be in a complex with Aβ. Cytoprotective cystatin C may provide a novel therapeutic avenue for protection against the long-term consequences of infection with P. aeruginosa.

Healthcare-Associated Infections in a Cardiac Surgery Service in Brazil

Objectives

The study aimed to determine the incidence of healthcare-associated infections (HAI) and their sites in a cardiac surgery service, as well as to determine if gender and age were risk factors for infection and to quantify mortality and increase in the hospital length of stay (LOS) due to HAI.

Methods

Medical records of patients who underwent cardiac surgery from January 2012 to January 2018 were retrospectively analyzed. Data on age, gender, mortality, occurrence of HAI during hospitalization, and LOS were collected. Continuous variables were analyzed using Student's t-test, while categorical variables were compared using Fisher's exact test or chi-square test.

Results

Among the 195 patients available, the HAI rate in our service was 22.6%, with female gender being a risk factor for infections (odds ratio [OR]=2.23; P=0.015). Age was also a significant risk factor for infections, with a difference in the mean age between the group with and without infection (P=0.02). The occurrence of an infectious process increased the LOS in 14 days (P<0.001) and resulted in higher mortality rates (P=0.112). A patient who has HAI was approximately 19 times more likely to remain hospitalized for more than nine days (P<0.001).

Conclusion

Age and gender were risk factors for the development of HAI and the occurrence of an infectious process during hospitalization significantly increases the LOS. These findings may guide future actions aimed at reducing the impact of HAI on the health system.

Preoperative Treatment of Malnutrition and Sarcopenia in Cardiac Surgery: New Frontiers

Cardiac surgery is performed more often in a population with an increasing number of comorbidities. Although these surgeries can be lifesaving, they disturb homeostasis and may induce a temporary overall loss of physiologic function. The required postoperative intensive care unit and hospital stay often lead to a mid- to long-term decline of nutritional and physical status, mental health, and health-related quality of life. Prehabilitation before elective surgery might be an opportunity to optimize the state of the patient. This article discusses current evidence and potential effects of preoperative optimization of nutrition and physical status before cardiac surgery.

Cardiothoracic Patients with Unilateral Vocal Fold Paralysis: Pneumonia Rates Following Injection Laryngoplasty

Objective:

Recurrent laryngeal nerve injury is a potential complication of cardiothoracic surgery and cause of unilateral vocal fold paralysis (UVFP). Injection laryngoplasty (IL) is an intervention offered to patients with UVFP to alleviate symptoms including dysphagia, dysphonia and weak cough. There is no definitive evidence that IL prevents pneumonia. In this study, we compare rates of pneumonia in patients with UVFP secondary to cardiothoracic surgery who did or did not undergo IL.

Methods:

A retrospective chart review identified patients diagnosed with UVFP by an otolaryngologist using flexible laryngoscopy following cardiothoracic surgery from January 1, 2008 to December 31, 2017. Each subject was grouped by IL status and assessed for subsequent pneumonia within 6 months of their diagnosis of UVFP. The association of IL with pneumonia was evaluated using Cox proportional hazards regression.

Results:

Of 92 patients who met inclusion criteria, 35 (38%) underwent IL and 57 (62%) did not. Twenty patients developed pneumonia, four who had undergone IL and 16 who had not; 12 patients developed aspiration pneumonia including two having undergone IL and 10 who had not. Those who had IL were less likely to develop total pneumonia compared to those who had not (HR = 0.33, P = .045). The protective effect of IL was not as clearly sustained when measuring for aspiration pneumonia, specifically (HR = 0.34; P = .10).

Discussion:

Injection laryngoplasty may reduce the risk of pneumonia in patients with UVFP secondary to cardiothoracic surgery; however, further research is needed to quantify the potential protective nature of IL in this patient population.

Level of evidence:

3 (A retrospective cohort study).

Exoenzyme Y Contributes to End-Organ Dysfunction Caused by Pseudomonas aeruginosa Pneumonia in Critically Ill Patients: An Exploratory Study

Pseudomonas aeruginosa is an opportunistic pathogen that causes pneumonia in immunocompromised and intensive care unit (ICU) patients. During host infection, P. aeruginosa upregulates the type III secretion system (T3SS), which is used to intoxicate host cells with exoenzyme (Exo) virulence factors. Of the four known Exo virulence factors (U, S, T and Y), ExoU has been shown in prior studies to associate with high mortality rates. Preclinical studies have shown that ExoY is an important edema factor in lung infection caused by P. aeruginosa, although its importance in clinical isolates of P. aeruginosa is unknown. We hypothesized that expression of ExoY would be highly prevalent in clinical isolates and would significantly contribute to patient morbidity secondary to P. aeruginosa pneumonia. A single-center, prospective observational study was conducted at the University of Alabama at Birmingham Hospital. Mechanically ventilated ICU patients with a bronchoalveolar lavage fluid culture positive for P. aeruginosa were included. Enrolled patients were followed from ICU admission to discharge and clinical P. aeruginosa isolates were genotyped for the presence of exoenzyme genes. Ninety-nine patients were enrolled in the study. ExoY was present in 93% of P. aeruginosa clinical isolates. Moreover, ExoY alone (ExoY⁺/ExoU⁻) was present in 75% of P. aeruginosa isolates, compared to 2% ExoU alone (ExoY⁻/ExoU⁺). We found that bacteria isolated from human samples expressed active ExoY and ExoU, and the presence of ExoY in clinical isolates was associated with end-organ dysfunction. This is the first study we are aware of that demonstrates that ExoY is important in clinical outcomes secondary to nosocomial pneumonia.

Virulent Pseudomonas aeruginosa infection converts antimicrobial amyloids into cytotoxic prions

Pseudomonas aeruginosa infection elicits the production of cytotoxic amyloids from lung endothelium, yet molecular mechanisms of host‐pathogen interaction that underlie the amyloid production are not well understood. We examined the importance of type III secretion system (T3SS) effectors in the production of cytotoxic amyloids. P aeruginosa possessing a functional T3SS and effectors induced the production and release of cytotoxic amyloids from lung endothelium, including beta amyloid, and tau. T3SS effector intoxication was sufficient to generate cytotoxic amyloid release, yet intoxication with exoenzyme Y (ExoY) alone or together with exoenzymes S and T (ExoS/T/Y) generated the most virulent amyloids. Infection with lab and clinical strains engendered cytotoxic amyloids that were capable of being propagated in endothelial cell culture and passed to naïve cells, indicative of a prion strain. Conversely, T3SS‐incompetent P aeruginosa infection produced non‐cytotoxic amyloids with antimicrobial properties. These findings provide evidence that (1) endothelial intoxication with ExoY is sufficient to elicit self‐propagating amyloid cytotoxins during infection, (2) pulmonary endothelium contributes to innate immunity by generating antimicrobial amyloids in response to bacterial infection, and (3) ExoY contributes to the virulence arsenal of P aeruginosa through the subversion of endothelial amyloid host‐defense to promote a lung endothelial‐derived cytotoxic proteinopathy.

Seasonality of postoperative pneumonia after coronary artery bypass grafting: A national inpatient sample study

BACKGROUND

The development of postoperative pneumonia following cardiac surgery is associated with significant morbidity and mortality. However, seasonal variation as a risk factor for the development of postoperative pneumonia remains to be investigated. We sought to investigate whether patients undergoing coronary artery bypass grafting (CABG) during "flu season" (Fall and Winter months) at increased risk of postoperative pneumonia.

MATERIALS AND METHODS

A retrospective cohort study of patients undergoing CABG in the National Inpatient Sample between 2005 and 2015 was completed. Concomitant diagnosis of pneumonia was defined as the primary outcome. Secondary outcomes were defined to include pneumonia secondary to several known pathogens. Outcomes with significant differences between Fall/Winter and Spring/Summer groups were further analyzed with additive time series decomposition. Odds ratios were generated and adjusted for age, sex, elective status, and 29 other Agency for Healthcare Research and Quality comorbidity measures.

RESULTS

A total of 238 757 and 277 941 patients undergoing CABG during Fall/Winter and Spring/Summer, respectively, were identified. A significantly increased risk of postoperative pneumonia (adjusted odds ratio [aOR] = 1.15) and infection with influenza (aOR = 4.08), Haemophilus influenzae (aOR = 1.40), and Streptococcus pneumoniae (aOR = 1.47) was observed among patients receiving CABG in Q1 (January-March) compared to Q3 (July-September).

CONCLUSIONS

There is a strong seasonality in the incidence of postoperative pneumonia after CABG which may persist across other cardiothoracic surgeries. In addition to optimizing infection control and perioperative care, cardiac surgeons should consider preoperative vaccination against seasonal influenza, H. influenzae, and S. pneumoniae to improve outcomes among high-risk patients.

Intraoperative Mechanical Ventilation and Postoperative Pulmonary Complications after Cardiac Surgery

BACKGROUND

Compared with historic ventilation strategies, modern lung-protective ventilation includes lower tidal volumes (VT), lower driving pressures, and application of positive end-expiratory pressure (PEEP). The contributions of each component to an overall intraoperative protective ventilation strategy aimed at reducing postoperative pulmonary complications have neither been adequately resolved, nor comprehensively evaluated within an adult cardiac surgical population. The authors hypothesized that a bundled intraoperative protective ventilation strategy was independently associated with decreased odds of pulmonary complications after cardiac surgery.

METHODS

In this observational cohort study, the authors reviewed nonemergent cardiac surgical procedures using cardiopulmonary bypass at a tertiary care academic medical center from 2006 to 2017. The authors tested associations between bundled or component intraoperative protective ventilation strategies (VT below 8 ml/kg ideal body weight, modified driving pressure [peak inspiratory pressure - PEEP] below 16 cm H2O, and PEEP greater than or equal to 5 cm H2O) and postoperative outcomes, adjusting for previously identified risk factors. The primary outcome was a composite pulmonary complication; secondary outcomes included individual pulmonary complications, postoperative mortality, as well as durations of mechanical ventilation, intensive care unit stay, and hospital stay.

RESULTS

Among 4,694 cases reviewed, 513 (10.9%) experienced pulmonary complications. After adjustment, an intraoperative lung-protective ventilation bundle was associated with decreased pulmonary complications (adjusted odds ratio, 0.56; 95% CI, 0.42-0.75). Via a sensitivity analysis, modified driving pressure below 16 cm H2O was independently associated with decreased pulmonary complications (adjusted odds ratio, 0.51; 95% CI, 0.39-0.66), but VT below 8 ml/kg and PEEP greater than or equal to 5 cm H2O were not.

CONCLUSIONS

The authors identified an intraoperative lung-protective ventilation bundle as independently associated with pulmonary complications after cardiac surgery. The findings offer insight into components of protective ventilation associated with adverse outcomes and may serve as targets for future prospective interventional studies investigating the impact of specific protective ventilation strategies on postoperative outcomes after cardiac surgery.

Ventilation after pancreaticoduodenectomy increases perioperative mortality: Identification of risk factors and their relevance in Germany that do not apply in England

BACKGROUND

Pre-operative risk factors for post-operative ventilation and their influence on survival after pancreaticoduodenectomy for malignancy are unknown.

METHODS

Totally 391 patients operated in Hannover, Germany were investigated with multivariable logistic regression and Cox regression modeling to identify independent risk factors for post-operative ventilation ≥6 h, patient survival and 90-day mortality. And 84 patients operated in Birmingham, United Kingdom were analyzed to assess the external relevance of findings.

RESULTS

Longer operations, history of thrombosis, intra-operative blood transfusion, lower estimated glomerular filtration rates (eGFR) and higher values of the age at operation divided by the Horovitz Quotient independently increased the risk of post-operative ventilation ≥ 6 h in German patients (n = 108; 27.6%) (P<0.050). Blood transfusion and lower pre-operative eGFR levels increased the risk of early death in German patients significantly and independently of established prognostic factors. A history of thrombosis and lower eGFR levels were also independent significant risk factors for 90-day mortality in German patients but not in English patients. None of the English patients received post-operative ventilation. Significantly more German patients were >75 years, had a history of thrombosis, received blood transfusions, and had significantly worse lung function parameters. pT4 tumors were detected in 18 German patients (4.6%), but not in the English patients.

CONCLUSIONS

Identified risk factors for post-operative ventilation are clinically relevant in Germany but not in England and may be used to lower mortality risk. The German and the English cohorts displayed significant differences in the approach to patient selection and early post-operative extubation.

Preoperative oral hygiene recommendation before open-heart surgery: patients' adherence and reduction of infections: a quality improvement study

Aim

To implement recommendations for oral hygiene before elective open-heart surgery in a thoracic surgery ward and to evaluate whether the number of patients who needed to be treated with antibiotics postoperatively was reduced.

Background

Healthcare systems are challenged to implement initiatives that reduce the development of nosocomial infections, to offer patients a safe and cost-efficient treatment and to reduce the use of antibiotics. Previous interventions have focused on staff behaviour in reducing postoperative infections. In this study, patients were recommended to carry out oral hygiene as recommended in a clinical guideline.

Methods

A quasiexperimental design with a control and an intervention group was used. Information on adherence to the recommendation was collected at admission. All medical information and prescriptions of antibiotics were obtained from patients’ medical records. Data were reported as intention to treat.

Results

Altogether 972 patients (506 controls and 466 interventions) were included in the study. Of the intervention patients, 405 (86.9%, 95% CI 83.3 to 89.8) reported that they had adhered to the oral hygiene recommendation. 64 (12.6%) control patients and 36 (7.7%) in the intervention group (p=0.015) were treated with antibiotics postoperatively.

Conclusions

It was feasible to involve patients in a programme for oral hygiene and thereby reduce the number of patients needing antibiotics after open-heart surgery and this might contribute to reducing costs.

Vitamin C to Improve Organ Dysfunction in Cardiac Surgery Patients-Review and Pragmatic Approach

The pleiotropic biochemical and antioxidant functions of vitamin C have sparked recent interest in its application in intensive care. Vitamin C protects important organ systems (cardiovascular, neurologic and renal systems) during inflammation and oxidative stress. It also influences coagulation and inflammation; its application might prevent organ damage. The current evidence of vitamin C's effect on pathophysiological reactions during various acute stress events (such as sepsis, shock, trauma, burn and ischemia-reperfusion injury) questions whether the application of vitamin C might be especially beneficial for cardiac surgery patients who are routinely exposed to ischemia/reperfusion and subsequent inflammation, systematically affecting different organ systems. This review covers current knowledge about the role of vitamin C in cardiac surgery patients with focus on its influence on organ dysfunctions. The relationships between vitamin C and clinical health outcomes are reviewed with special emphasis on its application in cardiac surgery. Additionally, this review pragmatically discusses evidence on the administration of vitamin C in every day clinical practice, tackling the issues of safety, monitoring, dosage, and appropriate application strategy.

Low tidal volume mechanical ventilation against no ventilation during cardiopulmonary bypass heart surgery (MECANO): study protocol for a randomized controlled trial

Background

Postoperative pulmonary complications are a leading cause of morbidity and mortality after cardiac surgery. There are no recommendations on mechanical ventilation associated with cardiopulmonary bypass (CPB) during surgery and anesthesiologists perform either no ventilation (noV) at all during CPB or maintain low tidal volume (LTV) ventilation. Indirect evidence points towards better pulmonary outcomes when LTV is performed but no large-scale prospective trial has yet been published in cardiac surgery.

Design

The MECANO trial is a single-center, double-blind, randomized, controlled trial comparing two mechanical ventilation strategies, noV and LTV, during cardiac surgery with CPB. In total, 1500 patients are expected to be included, without any restrictions. They will be randomized between noV and LTV on a 1:1 ratio. The noV group will receive no ventilation during CPB. The LTV group will receive 5 breaths/minute with a tidal volume of 3 mL/kg and positive end-expiratory pressure of 5 cmH2O. The primary endpoint will be a composite of all-cause mortality, early respiratory failure defined as a ratio of partial pressure of oxygen/fraction of inspired oxygen <200 mmHg at 1 hour after arrival in the ICU, heavy oxygenation support (defined as a patient requiring either non-invasive ventilation, mechanical ventilation or high-flow oxygen) at 2 days after arrival in the ICU or ventilator-acquired pneumonia defined by the Center of Disease Control. Lung recruitment maneuvers will be performed in the noV and LTV groups at the end of surgery and at arrival in ICU with an insufflation at +30 cmH20 for 5 seconds. Secondary endpoints are those composing the primary endpoint with the addition of pneumothorax, CPB duration, quantity of postoperative bleeding, red blood cell transfusions, revision surgery requirements, length of stay in the ICU and in the hospital and total hospitalization costs. Patients will be followed until hospital discharge.

Discussion

The MECANO trial is the first of its kind to compare in a double-blind design, a no-ventilation to a low-tidal volume strategy for mechanical ventilation during cardiac surgery with CPB, with a primary composite outcome including death, respiratory failure and postoperative pneumonia.

Trial registration

ClinicalTrials.gov, NCT03098524. Registered on 27 February 2017.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2321-9) contains supplementary material, which is available to authorized users.

Different strategies for mechanical VENTilation during CardioPulmonary Bypass (CPBVENT 2014): study protocol for a randomized controlled trial

Background

There is no consensus on which lung-protective strategies should be used in cardiac surgery patients. Sparse and small randomized clinical and animal trials suggest that maintaining mechanical ventilation during cardiopulmonary bypass is protective on the lungs. Unfortunately, such evidence is weak as it comes from surrogate and minor clinical endpoints mainly limited to elective coronary surgery. According to the available data in the academic literature, an unquestionable standardized strategy of lung protection during cardiopulmonary bypass cannot be recommended. The purpose of the CPBVENT study is to investigate the effectiveness of different strategies of mechanical ventilation during cardiopulmonary bypass on postoperative pulmonary function and complications.

Methods/design

The CPBVENT study is a single-blind, multicenter, randomized controlled trial. We are going to enroll 870 patients undergoing elective cardiac surgery with planned use of cardiopulmonary bypass. Patients will be randomized into three groups: (1) no mechanical ventilation during cardiopulmonary bypass, (2) continuous positive airway pressure of 5 cmH₂O during cardiopulmonary bypass, (3) respiratory rate of 5 acts/min with a tidal volume of 2–3 ml/Kg of ideal body weight and positive end-expiratory pressure of 3–5 cmH₂O during cardiopulmonary bypass. The primary endpoint will be the incidence of a PaO₂/FiO₂ ratio <200 until the time of discharge from the intensive care unit. The secondary endpoints will be the incidence of postoperative pulmonary complications and 30-day mortality. Patients will be followed-up for 12 months after the date of randomization.

Discussion

The CPBVENT trial will establish whether, and how, different ventilator strategies during cardiopulmonary bypass will have an impact on postoperative pulmonary complications and outcomes of patients undergoing cardiac surgery.

Trial registration

ClinicalTrials.gov, ID: NCT02090205. Registered on 8 March 2014.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2008-2) contains supplementary material, which is available to authorized users.

[Mortality from postoperative complications (failure to rescue) after cardiac surgery in a university hospital]

OBJECTIVE

This study analyses the rate of post-operative complications after cardiac surgery, the incidence of the failure to rescue (FR), and the relationship between complications and survival.

METHODS

The study included a total of 2,750 adult patients operated of cardiac surgery between January 2003 and December 2009. An analysis was made of 9 post-operative complications. Multiple logistic regression analysis was used to find independent variables associated with any of the selected complications. Survival was analysed with Kaplan-Meyer survival estimates. A risk-adjusted Cox proportional regression model was used to find out which complications were associated with mid-term survival.

RESULTS

Hospital mortality rate was 1.4% (95% CI: 1.0%-1.9%). Postoperative complications rate was 38.5% (36.7%-40.4%), and FR 3.6% (2.5%-4.9%). Urgent surgery (OR = 2.03; 1.52-2.72), chronic renal failure (OR = 1.50, 95%.CI: 1.25-1.80), and age ≥70 years (OR = 1.42; 1.20-1.68) were the variables that showed the highest strength of association with the selected complications. Survival at 5 years in the group of patients without complications was 93%, and in the group of patients with complications it was 83% (P<.0001). Postoperative complications associated with mid-term survival were pneumonia (HR = 2.6, 95% CI; 1.27-5.50), acute myocardial infarction (HR = 1.9; 1.10-2.30), and acute renal failure (HR = 1.7; 1.30-2.26).

CONCLUSIONS

The incidence of complications after cardiac surgery is around 40%, and was associated with an increase in hospital mortality, although FR was very low (3.6%; 95% CI: 2.5-4.9).

Hospital-acquired pneumonia in patients undergoing coronary artery bypass graft; comparison of the center for disease control clinical criteria with physicians' judgment

BACKGROUND

Following coronary artery bypass graft (CABG), patients are at high risk (3.2%-8.3%) for developing hospital-acquired pneumonia (HAP) with mortality rate of 24% to 50%. Some of routine features in patients undergoing CABG are similar to clinical criteria of Center of Disease Control (CDC) for diagnosis of pneumonia. This may lead to over-diagnosis of pneumonia in these patients.

OBJECTIVES

This study aimed to assess the frequency of CDC criteria for diagnosis of pneumonia in patients undergoing CABG.

PATIENTS AND METHODS

This study was performed on CABG candidates admitted to post cardiac surgery Intensive Care Unit (ICU) in a six-month period. Patient's records, Chest-X-Ray, and Laboratory tests were assessed for PNU1-CDC criteria for HAP diagnosis. At the same time, a physician who was unaware of the study protocol assessed the clinical diagnosis. Then the results were compared with CDC criteria-based diagnosis.

RESULTS

Of total 300 patients, 9 (3%) met CDC criteria for diagnosis of pneumonia while none of the cases were diagnosed as HAP according to the physicians' clinical diagnosis. All nine patients were discharged with proper general condition and no need of antibiotic therapy. This study showed that loss of consciousness, tachypnea, dyspnea, PaO2 < 60 mm Hg, PaO2/FiO2 < 240, and local infiltration in 24 hours of operation were misleading features of CDC criteria, which were not considered in physicians' clinical judgment to establish the diagnosis.

CONCLUSIONS

Our findings suggest that in Post-CABG patients, physicians could judge the occurrence of HAP more accurately in comparison to making the diagnosis based on CDC criteria alone. Expert physician may intentionally do not take some of these criteria into account according the patients' course of disease. Therefore, it is suggested that the value of these criteria in special group of patients like those undergoing CABG should be re-evaluated.