Development Of Postoperative Pneumonia Research Articles

Clinical Outcomes of Preserving Bronchial Arteries During Radical Esophagectomy: A Propensity-Score Matched Analysis.

Postoperative pneumonia is a common and major cause of mortality after radical esophagectomy. Intraoperative preservation of the bronchial arteries is often aimed at avoiding tracheobronchial ischemia; however, it is unknown whether this contributes to a reduction in postoperative pneumonia. We enrolled 348 consecutive patients who underwent radical esophagectomy for esophageal cancer at Toranomon Hospital from January 2011 to July 2018. We classified patients into a bronchial artery-resected (BA-R) group (n = 93) and a bronchial artery-preserved (BA-P) group (n = 255) and compared the incidence of postoperative pneumonia between the two groups. A propensity score-matching analysis for bronchial artery preservation versus resection was performed. Overall, 182 patients were matched. Univariate analysis of the propensity score-matched groups showed that Brinkman index ≥ 400, vital capacity (%VC) < 80%, and bronchial artery resection were associated with the development of postoperative pneumonia. Multivariate analysis revealed three significant factors associated with postoperative pneumonia: Brinkman index ≥ 400 [p = 0.006, odds ratio (HR) 3.302, 95% confidence interval (95% CI) 1.399-7.790], %VC < 80% (p = 0.034, HR 6.365, 95% CI 1.151-35.205), and bronchial artery resection (p = 0.034, HR 2.131, 95% CI 1.060-4.282). The incidence of postoperative complications (CD grade III) was higher in the BA-R group (BA-R 42.8% versus BA-P 27.5%, p = 0.030). There was no significant difference in overall survival between the two groups at 5 years (BA-R 63.1% versus BA-P 72.1%, p = 0.130). Preserving the bronchial artery is associated with a decreased incidence of postoperative pneumonia.

546. THE IMPACT OF PREOPERATIVE DENTITION ON POSTOPERATIVE SPUTUM SURVEILLANCE CULTURE AND POSTOPERATIVE PNEUMONIA IN PATIENTS WITH ESOPHAGEAL CANCER

Abstract Preoperative dental cleaning and treatment are increasingly performed as part of perioperative management, and postoperative pneumonia has been reported to be reduced by these dental interventions in patients with esophageal cancer. However, few studies have surveyed the impact of dentition on postoperative sputum culture and pneumonia. Fifty-five consecutive patients who underwent subtotal esophagectomy at Center Hospital of the National Center for Global Health and Medicine between November 2015 and August 2020 were included. Salvage cases, two-stage procedures, and cases with inadequate dental findings were excluded. The number of lost teeth was investigated, and the relationship between sputum surveillance cultures collected on the first to fourth day after surgery and the development of postoperative pneumonia was analyzed. Postoperative sputum surveillance culture revealed pathogenic organisms in 31 (56%) patients. Candida species/P. aeruginosa/Klebsiella species/E. cloacae/S. maltophilia/S. pneumoniae/S. aureus were detected in 27/13/9/7/5/4/4/4%, respectively. Pathogenic organisms were detected significantly more frequently in cases with more than ten lost teeth (p&amp;lt;0.01, odds ratio 6.42, 95% CI 1.58-26.1). Twelve patients (22%) had postoperative pneumonia with Clavien-Dindo grade 2 or higher. Postoperative pneumonia occurred significantly more frequently in patients with more than ten lost teeth (p=0.03, odds ratio 4.62, 95% CI 1.20-17.8). Postoperative pneumonia occurred significantly more frequently in patients in whom pathogens were detected (p=0.046, odds ratio 5.75, 95% CI 1.12-29.4). Patients with many lost teeth tended to have pathogens detected in early postoperative surveillance cultures before the onset of pneumonia and have more risk of developing postoperative pneumonia.

Relationship Between Preoperative Hypoalbuminemia and Postoperative Pneumonia Following Geriatric Hip Fracture Surgery: A Propensity-Score Matched and Conditional Logistic Regression Analysis.

BackgroundPneumonia is a devastating complication following geriatric hip fracture surgery, and preoperative hypoalbuminemia may be a potentially modifiable factor leading to improved outcome. This study aimed to quantify the relationship between preoperative hypoalbuminemia and postoperative pneumonia.MethodsWe retrospectively reviewed the medical records of elderly patients (≥60 years) who underwent surgeries for hip fracture in a tertiary referral center between 2016 and 2020. According to the preoperative serum albumin level, they were divided into two groups: <35 g/ L and ≥35 g/ L. To reduce potential confounding, propensity score matching (PSM) in a 1:1 ratio was performed, with the caliper value set as 0.002; and further conditional logistic regression analysis was used to control the other potential confounders to determine the association strength.ResultsAmong 3,147 eligible patients included, PSM yielded 1,318 matched patients, with 659 in each respective group, suggesting significantly improved balance in most variables (standardized mean deviation improvement range, 20.7% to 99.1%), except for basophil count. The conditional logistic regression analysis, adjusted for PS and other intra- or post-operative variables, showed 6.18-fold (relative ratio, 6.18; 95% CI, 3.15–11.98; P<0.001) increased risk of postoperative pneumonia associated with preoperative hypoalbuminemia.ConclusionPreoperative hypoalbuminemia was identified to be independently and highly associated with development of postoperative pneumonia in elderly patients undergoing hip fracture surgeries. However, whether the patients who had such condition may benefit from preoperative targeted nutritional support needs to be clarified by more prospective studies.

Preoperative maximum phonation time as a predictor of pneumonia in patients undergoing esophagectomy

Esophagectomy is a highly invasive procedure, associated with several postoperative complications including pneumonia, anastomotic leakage, and sepsis, which may result in multiorgan failure. Pneumonia is considered a major predictor of poor long-term prognosis, so its prevention is important for patients undergoing surgery for esophageal cancer. The subjects of this study were 137 patients who underwent esophagectomy at Keio University Hospital, Tokyo, Japan, between January, 2012 and December, 2016. Patients who underwent R0 or R1 resection or esophagectomy with organ excision were included. Patients who underwent salvage surgery or resection of recurrent laryngeal nerve, and those with preoperative recurrent laryngeal nerve palsy, were excluded. We investigated the effect of the maximum phonation time on the development of postoperative pneumonia. Pneumonia developed more frequently in patients with a long operative time, clinically left recurrent nerve lymph node metastasis, and a short preoperative maximum phonation time (p = 0.074, 0.046, and 0.080, respectively). Pneumonia was also more common in men with an abnormal maximum phonation time (p = 0.010). The maximum phonation time is a significant predictor of postoperative pneumonia after esophagectomy in men.

Prevention of postoperative pneumonia by perioperative oral care in patients with esophageal cancer undergoing surgery: a multicenter retrospective study of 775 patients.

Postoperative pneumonia is one of the major complications after esophageal cancer surgery. The risk factors associated with postoperative pneumonia are poor general health, smoking, decreased pulmonary function, diabetes mellitus, surgical stress, old age, postoperative aspiration, and oral hygiene. In this study, we examined the effect of perioperative oral care on reducing postoperative pneumonia since the evidence to-date is not clear. A multicenter, retrospective investigation of the relationship between perioperative oral care and incidence of postoperative pneumonia in patients undergoing esophageal cancer surgery was conducted. A total of 775 patients who underwent thoracoscopic esophageal resection at 25 hospitals between 2016 and 2017 were enrolled in the study. Various factors were examined for correlation with development of postoperative pneumonia. Multivariate analysis showed that old age, smoking habit, lower hemoglobin, higher creatinine, postoperative dysphagia, and lack of oral care intervention were independent risk factors for pneumonia. Oral care was more effective in preventing pneumonia in hospitals in which the incidence of postoperative pneumonia was lower than 20%, while it was not effective in hospitals in which the incidence was higher than 20%. Results of the study suggest that it is recommended to carry out perioperative oral care in esophageal cancer surgery.

Influence of Postoperative Pneumonia on Esophageal Cancer Survival and Recurrence.

Postoperative pneumonia after esophageal cancer can lead to additional pain, prolonged hospital stay, and respiratory failure. These adverse events might lead to early recurrence and/or death. We investigated the influence of postoperative pneumonia on the esophageal cancer survival and recurrence after curative surgery. This study included 122 patients who underwent curative surgery for esophageal cancer between 2008 and 2018. The patients were classified into: i) those with postoperative pneumonia (pneumonia group) and ii) those without postoperative pneumonia (non-pneumonia group). The risk factors for the overall survival (OS) and recurrence-free survival (RFS) were identified. The rate of postoperative pneumonia was measured by the revised Uniform Pneumonia Score. Postoperative complications were found in 34 of the 122 patients (27.9%). The OS rate at 5 years following surgery was 28.2% in the pneumonia group and 55.1% in the non-pneumonia group (p=0.006). The RFS rate at 5 years after surgery was 18.9% in the pneumonia group and 49.2% in the non-pneumonia group (p=0.061). A multivariate analysis showed that postoperative pneumonia was a significant independent risk factor for OS. The development of postoperative pneumonia was a risk factor for a decreased overall survival in patients who underwent curative surgery for esophageal cancer. The surgical procedure, perioperative care and surgical strategy should be carefully planned in order to avoid postoperative pneumonia.

Development of Postoperative Pneumonia After Endovascular Aortic Aneurysm Repair is Associated with an Increased Length of Intensive Care Unit Stay.

ObjectiveEndovascular aortic aneurysm repair (EVAR) has increasingly replaced open aortic surgery for treatment of abdominal aortic aneurysms (AAA). One of the key advantages of EVAR is the reduced length of intensive care unit (ICU) stay and hospital stay. This study aimed to identify the risk factors associated with increased ICU length of stay (LOS) after EVAR.MethodsThe American College of Surgeons (ACS-NSQIP) database for the year 2013 was used. All patients who underwent EVAR were divided into two groups: ICU LOS <1 day vs. ≥1 day. Preoperative, intraoperative, and postoperative factors were compared between these two groups utilizing bivariate logistic regression analysis. Multivariable logistic regression analysis was then used to identify factors that were independently associated with ICU LOS ≥1 day after EVAR.ResultsA total of 2,468 patients (18.7% females, 81.3% males) were identified. Group 1 (ICU LOS <1 day) = 1,535 patients and Group 2 (ICU LOS ≥1 day) = 933 patients. Multivariable analysis identified the following factors to be associated with ICU LOS ≥1 day: ruptured AAA (OR 3.88, CI 1.97-7.65), the American Society of Anesthesiology (ASA) score of 4-5 (OR 2.82, CI 1.50-5.31), operative time ≥180 minutes (OR 2.10, CI 1.51-2.93), bilateral groin cut down (OR 1.37, CI 1.10-1.71), juxta-renal AAA (OR 1.65, CI 1.16-2.35), renal artery stent (OR 2.13, CI 1.42-3.21), aortic stent (OR 2.39, CI 1.60-3.55), emergency surgery (OR 2.56, CI 1.94-3.38), need for blood transfusion (OR 3.11, CI 2.08-4.65) and postoperative pneumonia (OR 7.04, CI 1.95-25.45).ConclusionVariables identified above can be used to predict the cohort of EVAR patients which will likely require ICU for ≥1 day. Development of postoperative pneumonia is associated with a 7.04 times increase in ICU LOS ≥1 day.

Development of Postoperative Pneumonia after Endovascular Aortic Aneurysm Repair Is Associated with an Increased Length of ICU Stay

Development of Postoperative Pneumonia after Endovascular Aortic Aneurysm Repair Is Associated with an Increased Length of ICU Stay

An Unexpected Masquerader: A Case of Acute Fulminant Colitis Secondary to Ulcerative Colitis

Inflammatory bowel disease (IBD) has a bimodal age distribution with a second peak between 50 and 80 years. We report a case of fulminant colitis in a 74-year-old Caucasian Male presenting with diarrhea and intermittent left lower quadrant pain. His medical history was pertinent for an episode of acute complicated sigmoid diverticulitis with perforation, and abscess formation 2-months prior. A CT-guided drainage was performed then and he was treated with a course of piperacillin-tazobactam and amoxicillin-clavulanic acid. A sigmoidoscopy was performed 4 weeks later and findings included a sigmoid stricture, pseudo-membranes and a 4 cm sigmoid tubular adenoma; which was resected. A Clostridium Difficile test was positive and the patient was started on oral vancomycin. The patient reported worsening of his symptoms and developed hematochezia. His repeat diagnostic evaluation was remarkable for a mild neutrophilic leukocytosis of 13,200 cells/mm3, marked lactic acidosis and negative C. Difficile testing. A CT-scan of the abdomen revealed diffuse colitis and a repeat flexible sigmoidoscopy demonstrated ischemic changes and multiple areas of friable mucosa. The patient further deteriorated and underwent a total colectomy with ileostomy given concern for ischemic colitis. Saccharomyces Cervisiae IgA and IgG titers were positive and ANCA testing was negative. Pathology results revealed chronic active colitis with cryptitis, crypt abscesses, and absence of granulomas with multiple diverticula. Morphology was consistent with a diagnosis of fulminant colitis secondary to ulcerative colitis. The patient underwent a complicated post-operative course with the development of postoperative pneumonia, pulmonary edema and ventilator dependent respiratory failure requiring tracheostomy placement. This case serves to illustrate the importance of recognizing the bimodal distribution of inflammatory bowel disease (IBD), entertaining the diagnosis in elderly patients presenting with colitis, and the importance of a multi-disciplinary approach to establishing a diagnosis of IBD involving clinicians and pathologists. The presence of an anchoring bias to the diagnosis of acute diverticulitis when the first sigmoidoscopy was performed and the attribution of the patient's colitis to C. Difficile colitis and later ischemic colitis led to a late diagnosis of IBD with significant morbidity noted. The case also highlights the utility of serologies in diagnosing IBD.

PS02.202: CLINICAL SIGNIFICANCE OF MEASUREMENT OF SKELETAL MUSCLE VOLUME AND SERUM NUTRITIONAL MARKERS IN ESOPHAGEAL CANCER PATIENTS

Abstract Background Some studies reported the association of muscle mass or nutritional state with development of postoperative morbidity. However, it remains unknown whether body composition or nutritional state influences upon clinical outcome in esophageal cancer (EC) patients undergoing surgery following neoadjuvant chemotherapy (NAC). Methods A total of 100 EC patients who undergone NAC followed by curative surgical resection in our hospital from 2011 to 2013 was analyzed. The cross-sectional area of psoas was measured by computed tomography at third lumbar vertebra and the Psoas Muscle Index [PMI: total psoas area at L3/(height × height)] was calculated. Pre- and post-NAC PMI in addition to prognostic nutritional index (PNI), modified Glasgow prognostic scale (mGPS), and neutrophil/lymphocyte ratio (N/L) as an inflammation or nutrition marker were evaluated in terms of their association with development of NAC adverse event, postoperative complications and long-term survival. Results The PMI significantly decreased during chemotherapy from 705.5 to 682.7 cm2/m2 (P = 0.0008). Pre-NAC PMI (low vs high group, cutoff: 6.36cm2/m2 for male, 3.92cm2/m2 for female) was significantly associated with serum albumin (3.5 vs 3.8g/dl P = 0.0064) and body mass index (19.6 vs 22.2kg/m2P &lt; 0.001), and clinical response to NAC (response rate 66.7 vs 87.1% P = 0.02). Post-NAC PMI, meanwhile, correlated with development of postoperative pneumonia [Clavien-Dindo (C-D) classification grade &gt; II] (35.0 vs 8.3% P = 0.0009) and expectoration disorder of sputum (C-D classification grade &gt; III) (28.6 vs 10.5% P = 0.027) while neither pre- or post PMI were predictive of patient survival. Regarding serum nutritional markers, pre-NAC PNI and mGPS correlated with NAC-induced neutropenia [low vs high PNI (cutoff: 40): 100 vs 87% P = 0.019] and diarrhea (mGPS 0/1 vs 2: 27.4 vs 80.0% P = 0.017) while post-NAC mGPS (mGPS 0 vs 1/2) was predictive of development of postoperative pneumonia (11.5 vs 30.8%, P = 0.018) and expectoration disorder of sputum (10.7 vs 27.8%, P = 0.037), respectively. Notably, post-NAC mGPS (mGPS 0 vs 1/2: 76.4 vs 65.4%, P = 0.039) and N/L (N/L ≥ 2.5 vs &lt; 2.5: 43.5 vs 82.1% P = 0.006) showed the significant association with 2-year overall survival. Conclusion Pre- and post-NAC PMI in addition to serum inflammation/nutrition markers might be clinically useful in predicting outcome of multidisciplinary treatments for EC patients. Disclosure All authors have declared no conflicts of interest.

P3.16-010 Preoperative Six-Minute Walk Distance Is Associated with Complications of Pneumonia after Lung Resection

Postoperative pulmonary complications such as pneumonia are significant negative predictors of short- and long-term survival after thoracic surgery. A preoperative cardio-pulmonary function is known as a predictor for postoperative pulmonary complications in patients with lung cancer. However, little is known about the relationship between preoperative exercise capacity and complication of pneumonia after lung resection. The 6-min walk distance (6MWD) measured by the 6-min walk test (6MWT) is a simple, safe, and inexpensive field test that can be used to evaluate the functional exercise capacity. We examined the association between preoperative 6MWD and development of postoperative pneumonia. A retrospective study was conducted on patients with malignant lung tumors who were scheduled to undergo lung resection at Nagoya University Hospital from January 2014 to December 2015 (Institutional Review Board approval No. 2015-0413). Preoperative pulmonary function tests and 6MWT were assessed. A logistic regression model and receiver operating characteristic (ROC) curves were used to analyze clinical variables and compare the performance on 6MWD and percentages of predicted values of forced expiratory volume in 1 s (%FEV1) and diffusion capacity of the lung for carbon monoxide (%DLco). The data from a total 321 patients including 283 with primary lung cancer and 38 with metastatic lung tumors were analyzed. Preoperative 6MWD significantly correlated with age, FEV1, forced vital capacity (FVC), %DLco, and serum albumin level. Pneumonia developed in 13 patients (4.0%) and the 6MWD of patients with pneumonia was significantly lower than that of patients without (413.9±89.0 vs. 495.2±93.2 m, p=0.002). Incidences of smoking history and comorbidity of COPD and interstitial lung disease were significantly higher and %FEV1, FEV1/FVC, %DLco, and serum albumin level were significantly lower in patients with pneumonia than in those without. Length of hospital stay after surgery was significantly longer in patients with pneumonia than in those without (30.4±29.6 vs. 7.4±7.0 days, p<0.001). In ROC analysis, 6MWD ≤450 m was a threshold for predicting postoperative pneumonia with 69.2% sensitivity and 71.1% specificity. A 6MWD ≤450 m, %FEV1 <80%, %DLco <80%, serum albumin <3.5 g/dL, and blood loss during surgery >200 g were significantly associated with development of postoperative pneumonia in a logistic model adjusted by age, sex, and primary lung cancer. Preoperative 6MWD is associated with development of pneumonia after lung resection for malignancies. Preoperative 6MWT is a useful screening tool in patients with primary and metastatic lung tumors.

Nondepolarizing Neuromuscular Blocking Agents, Reversal, and Risk of Postoperative Pneumonia

(Abstracted from Anesthesiology, 125:647–655, 2016) The aim of the study was to investigate 2 questions: first, whether there is an association between the use of nondepolarizing neuromuscular-blocking agents (NMBAs) during surgery and the development of postoperative pneumonia (POP); second, whether there is an increased incidence of POP in patients who did not receive reversal of their nondepolarizing NMBAs. The authors studies 13,100 pertinent surgeries at Vanderbilt University Medical Center between July 8, 2005, and September 30, 2013, and compared postoperative patients who received nondepolarizing NMBAs such as cisatracurium, rocuronium, or vecuronium (n = 1455) with patients who did not receive these agents (n = 1455).

The development of early-onset ventilator-associated pneumonia after cardiac surgery with cardiopulmonary bypass is associated with toll-like receptor 4 signal transduction pathways.

We evaluated the hypothesis that early-onset ventilator-associated pneumonia (VAP) after cardiac surgery with cardiopulmonary bypass (CPB) requires Toll-like receptor 4 (TLR4)-dependent signaling pathways. We enrolled 50 patients undergoing mitral and aortic double valve replacement, collecting left atrial blood samples from all patients preoperatively (T1), when opening the atrial septum (T2), closing the atrial septum (T3), and at the end of CPB (T4). TLR4 expression on monocytes and lymphocytes was detected immediately with flow cytometry. Serum levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-10 (IL-10) were measured using enzyme-linked immunosorbent assays (ELISA). Data from flow cytometry, ELISA, and the clinical outcomes in the two groups were evaluated and compared. Seventeen patients were included for analysis, and assigned to group A (without early-onset VAP, n = 10) and group B (with early-onset VAP, n = 7). TLR4 expression on lymphocytes in group B at T1, T3, and T4 were significantly higher than those in group A. Serum levels of IL-10 in group A at T4 were significantly higher than for group B. We found characteristic patterns in TLR4 expression on lymphocytes in left atrial blood of patients undergoing cardiac surgery with CPB. Our findings clarify the role of TLR4 and its association with the development of postoperative pneumonia.

Relationship Between Cytokine Gene Polymorphisms and Risk of Postoperative Pneumonia with Esophageal Cancer

BackgroundWe retrospectively evaluated the relationship between cytokine gene polymorphisms and development of postoperative pneumonia after esophagectomy. MethodsIn 120 patients who underwent esophagectomy, serum samples were obtained to measure levels of serum interleukin (IL)-6 and IL-10 at four time points (preoperatively, postoperative day (POD)0, POD1, and POD3). DNA extracted from peripheral blood in all patients was analyzed to determine polymorphisms of cytokines such as tumor necrosis factor-α -1031 T/C, IL-1β -511C/T, IL-6 -634C/G, and IL-10 -819 T/C. ResultsPostoperative pneumonia arose in 34 patients (28.3 %). Perioperative serum IL-10 levels were significantly higher for IL-10 -819 C/T + C/C genotypes than for T/T genotypes (POD0 16.7±2.84 vs. 8.54±0.87 pg/ml, p = 0.0002; POD1 14.0±2.64 vs. 8.8±0.87 pg/ml, p = 0.0143; POD3 8.9±2.67 vs. 4.4±0.52 pg/ml, p = 0.0076). The frequency of the IL-10 -819 T/T genotype was significantly higher in patients with postoperative pneumonia than in patients without pneumonia (p = 0.0323). Multivariate analysis of factors such as sex, smoking, length of operation, field of lymph node dissection, and IL-10 polymorphism identified IL-10 polymorphism as independent predictor of postoperative pneumonia. ConclusionsPatients with IL-10 -819 T/T genotype may be at high risk for postoperative pneumonia after esophagectomy.

Antimicrobial activity and clinical effectiveness of sisomicin: an evaluation of the literature (1995–2011)

The authors sought to evaluate whether sisomicin has a place in the current therapeutic armamentarium. PubMed and Scopus databases were systematically searched. Ten cohort studies and 11 case reports and case series were included evaluating, in total, 383 Gram-positive and 83 Gram-negative isolates. Sisomicin was active in vitro against 41% of Enterococcus spp., 97% of Staphylococcus spp. and was the most active in vitro (74%) aminoglycoside against Stenotrophomonas maltophilia isolates in one study. Regarding clinical effectiveness, sisomicin topical cream was effective in all 290 patients with pyoderma in one study, while the intravenous formulation of sisomicin was effective as prophylaxis for the development of postoperative pneumonia in 91% of lung surgery patients in another. In conclusion, sisomicin may be useful against certain pathogens; however, clinical data are scarce. Further studies are needed and may shed additional light in this area.

Identification of Patients at Risk for Postoperative Respiratory Complications Using a Preoperative Obstructive Sleep Apnea Screening Tool and Postanesthesia Care Assessment

Patients with obstructive sleep apnea are at risk for perioperative morbidity. The authors used a screening prediction model for obstructive sleep apnea to generate a sleep apnea clinical score (SACS) that identified patients at high or low risk for obstructive sleep apnea. This was combined with postanesthesia care unit (PACU) monitoring with the aim of identifying patients at high risk of postoperative oxygen desaturation and respiratory complications. In this prospective cohort study, surgical patients with a hospital stay longer than 48 h who consented were enrolled. The SACS (high or low risk) was calculated; all patients were monitored in the PACU for recurrent episodes of bradypnea, apnea, desaturations, and pain-sedation mismatch. All patients underwent pulse oximetry postoperatively; complications were documented. Chi-square, two-sample t test, and logistic regression were used for analysis. The oxygen desaturation index (number of desaturations per hour) was calculated. Oxygen desaturation index and incidence of postoperative cardiorespiratory complications were primary endpoints. Six hundred ninety-three patients were enrolled. From multivariable logistic regression analysis, the likelihood of a postoperative oxygen desaturation index greater than 10 was increased with a high SACS (odds ratio = 1.9, P < 0.001) and recurrent PACU events (odds ratio = 1.5, P = 0.036). Postoperative respiratory events were also associated with a high SACS (odds ratio = 3.5, P < 0.001) and recurrent PACU events (odds ratio = 21.0, P < 0.001). Combination of an obstructive sleep apnea screening tool preoperatively (SACS) and recurrent PACU respiratory events was associated with a higher oxygen desaturation index and postoperative respiratory complications. A two-phase process to identify patients at higher risk for perioperative respiratory desaturations and complications may be useful to stratify and manage surgical patients postoperatively.

Invited commentary

Invited commentary

Preoperative Concentrations of suPAR and MBL Proteins Are Associated with the Development of Pneumonia after Elective Surgery for Colorectal Cancer

The urokinase-type plasminogen activation (uPA) system and the mannan-binding lectin (MBL) complement activation pathway are involved in regulation of immune responses. The blood concentrations of these molecules in the individual patient thus could be related to the risk of postoperative infectious complications. The aim of this retrospective study was to determine the association between the soluble uPA receptor (suPAR) and MBL concentrations and the development of postoperative bacterial infectious complications. Blood samples were drawn preoperatively from 544 patients scheduled to undergo primary resection for colorectal cancer. Plasma suPAR was determined by enzyme-linked immunosorbent assay and serum MBL by time-resolved immunofluorescent assay. The following infectious events were recorded during the first month after surgery: surgical site or perineal infection or both, intra-abdominal abscess, anastomotic leakage, pneumonia, and blood stream infection. Data on perioperative blood transfusions in addition to clinical baseline characteristics were included as well. The numbers of surgical site infections, intra-abdominal abscesses, anastomotic leakages, pneumonias, and blood stream infections were 51, 20, 32, 78, and 19, respectively. Univariate analysis showed that elevated concentrations of suPAR (p = 0.01; odds ratio [OR] 2.2; 95% confidence interval [CI] 1.2, 3.9), low concentrations of MBL (p = 0.047; OR 0.9; 95% CI 0.8, 1.0), and perioperative blood transfusion (p = 0.006; OR 1.5; 95% CI 1.1, 2.0) were associated with the development of pneumonia. Significant associations with other bacterial infections could not be demonstrated. Multivariate analysis including disease stage, sex, and age showed that suPAR, MBL, and perioperative blood transfusion were significantly and independently associated with postoperative pneumonia. Concentrations of suPAR and MBL, in addition to perioperative blood transfusion, were significantly associated with the development of postoperative pneumonia. No other statistically significant relationships could be demonstrated. Thus, further research should be directed to clarifying the biological role of these two molecules in the development of postoperative pneumonia.

Intervention at the Level of the Neuroendocrine–Immune Axis and Postoperative Pneumonia Rate in Long-term Alcoholics

Postoperative pneumonia is three to four times more frequent in patients with alcohol use disorders followed by prolonged intensive care unit (ICU) stay. Long-term alcohol use leads to an altered perioperative hypothalamus-pituitary-adrenal (HPA) axis and immunity. The aim of this study was to evaluate HPA intervention with low-dose ethanol, morphine, or ketoconazole on the neuroendocrine-immune axis and development of postoperative pneumonia in long-term alcoholic patients. In this randomized, double-blind controlled study, 122 consecutive patients undergoing elective surgery for aerodigestive tract cancer were included. Long-term alcohol use was defined as consuming at least 60 g of ethanol daily and fulfilling the Diagnostic and Statistical Manual of Mental Disorders IV criteria for either alcohol abuse or dependence. Nonalcoholic patients were included but only as a descriptive control. Perioperative intervention with low-dose ethanol (0.5 g/kg body weight per day), morphine (15 mug/kg body weight per hour), ketoconazole (200 mg four times daily), and placebo was started on the morning before surgery and continued for 3 d after surgery. Blood samples to analyze the neuroendocrine-immune axis were obtained on the morning before intervention and on Days 1, 3, and 7 after surgery. In long-term alcoholic patients, all interventions decreased postoperative hypercortisolism and prevented impairment of the cytotoxic T-lymphocyte type 1:type 2 ratio. All interventions decreased the pneumonia rate from 39% to a median of 5.7% and shortened intensive care unit stay by 9 d (median) compared with the placebo-treated long-term alcoholic patients. Intervention at the level of the HPA axis altered the immune response to surgical stress. This resulted in decreased postoperative pneumonia rates and shortened intensive care unit stay in long-term alcoholic patients.

Intratracheal long-term pH monitoring: a new method to evaluate episodes of silent acid aspiration in patients after esophagectomy and gastric pull up.

Aspiration of gastric contents is considered a leading cause of postoperative pulmonary complications after esophagectomy and gastric pull up but has been difficult to diagnose. We used intratracheal long-term pH monitoring to evaluate the prevalence of aspiration of gastric contents in patients undergoing these operations. Continuous intratracheal pH monitoring was carried out during the first 72 postoperative hours in 16 patients with esophageal carcinoma who had undergone esophagectomy and gastric pull up. A drop in the pH to less than 4 was defined as an episode of acid aspiration. All patients except one tolerated the probe without any difficulties. Episodes of acid aspiration could be detected in 12 (80%) of 15 patients (5 of 8 after transhiatal esophagectomy, 7 of 7 after transthoracic esophagectomy, 2 of 5 with reconstruction in the anterior mediastinum, and 9 of 10 with reconstruction in the posterior mediastinum). The number of aspiration episodes was significantly higher during postoperative day 1 (P=0.03) compared to postoperative days 2 and 3. Two patients developed pneumonia later in the postoperative course. Both of them had several episodes of acid aspiration detected by pH monitoring immediately postoperatively. Intratracheal pH monitoring is a safe, feasible, and well-tolerated method for detecting episodes of acid aspiration after esophagectomy and gastric pull up. Aspiration of gastric contents is a common phenomenon particularly during the first 24 postoperative hours after transthoracic esophagectomy and gastric pull up in the posterior mediastinum and appears to correlate with the development of postoperative pneumonia.