Post-pneumonectomy pulmonary edema: analysis and risk factors

Effect of inferior vena cava respiratory variability-guided fluid therapy after laparoscopic hepatectomy: a randomized controlled clinical trial

BACKGROUND

After major liver resection, the volume status of patients is still undetermined. However, few concerns have been raised about postoperative fluid management. We aimed to compare gut function recovery and short-term prognosis of the patients after laparoscopic liver resection (LLR) with or without inferior vena cava (IVC) respiratory variability-directed fluid therapy in the anesthesia intensive care unit (AICU).

METHODS

This randomized controlled clinical trial enrolled 70 patients undergoing LLR. The IVC respiratory variability was used to optimize fluid management of the intervention group in AICU, while the standard practice of fluid management was used for the control group. The primary outcome was the time to flatus after surgery. The secondary outcomes included other indicators of gut function recovery after surgery, postoperative length of hospital stay (LOS), liver and kidney function, the severity of oxidative stress, and the incidence of severe complications associated with hepatectomy.

RESULTS

Compared with patients receiving standard fluid management, patients in the intervention group had a shorter time to anal exhaust after surgery (1.5 ± 0.6 days vs. 2.0 ± 0.8 days) and lower C-reactive protein activity (21.4 [95% confidence interval (CI): 11.9-36.7] mg/L vs. 44.8 [95%CI: 26.9-63.1] mg/L) 24 h after surgery. There were no significant differences in the time to defecation, serum concentrations of D-lactic acid, malondialdehyde, renal function, and frequency of severe postoperative complications as well as the LOS between the groups.

CONCLUSION

Postoperative IVC respiratory variability-directed fluid therapy in AICU was facilitated in bowel movement but elicited a negligible beneficial effect on the short-term prognosis of patients undergoing LLR.

TRIAL REGISTRATION

ChiCTR-INR-17013093.

Restricted, optimized or liberal fluid strategy in thoracic surgery: A narrative review

Perioperative fluid balance has a major impact on clinical and functional outcome, regardless of the type of interventions. In thoracic surgery, patients are more vulnerable to intravenous fluid overload and to develop acute respiratory distress syndrome and other complications. New insight has been gained on the mechanisms causing pulmonary complications and the role of the endothelial glycocalix layer to control fluid transfer from the intravascular to the interstitial spaces and to promote tissue blood flow. With the implementation of standardized processes of care, the preoperative fasting period has become shorter, surgical approaches are less invasive and patients are allowed to resume oral intake shortly after surgery. Intraoperatively, body fluid homeostasis and adequate tissue oxygen delivery can be achieved using a normovolemic therapy targeting a “near-zero fluid balance” or a goal-directed hemodynamic therapy to maximize stroke volume and oxygen delivery according to the Franck–Starling relationship. In both fluid strategies, the use of cardiovascular drugs is advocated to counteract the anesthetic-induced vasorelaxation and maintain arterial pressure whereas fluid intake is limited to avoid cumulative fluid balance exceeding 1 liter and body weight gain (~1-1.5 kg). Modern hemodynamic monitors provide valuable physiological parameters to assess patient volume responsiveness and circulatory flow while guiding fluid administration and cardiovascular drug therapy. Given the lack of randomized clinical trials, controversial debate still surrounds the issues of the optimal fluid strategy and the type of fluids (crystalloids versus colloids). To avoid the risk of lung hydrostatic or inflammatory edema and to enhance the postoperative recovery process, fluid administration should be prescribed as any drug, adapted to the patient's requirement and the context of thoracic intervention.

A Multiple-Center Nomogram to Predict Pneumonectomy Complication Risk for Non-Small Cell Lung Cancer Patients

OBJECTIVE

This study aimed to construct a nomogram to quantitatively predict pneumonectomy complication risks for non-small cell lung cancer (NSCLC) patients.

METHODS

Data from 1052 NSCLC patients who underwent pneumonectomy were retrospectively retrieved from the databases of three thoracic centers. Multivariable logistic regression was used to investigate postoperative morbidity predictors. Clinical parameters and operative features were analyzed using univariable and multivariable logistic regression analyses, and a nomogram to predict the risk of postoperative complications was constructed using bootstrap resampling. A receiver operating characteristic (ROC) curve was used to estimate the discrimination power for the nomogram.

RESULTS

A total of 212 patients (20.2%) had major complications. After regression analysis, forced expiratory volume in 1 s, Charlson Comorbidity Index score, male sex, and right-sided pneumonectomy were identified and entered into the nomogram. The nomogram showed a robust discrimination, with an area under the ROC curve of 0.753 (95% confidence interval 0.604-0.818). The calibration curves for the probability of postoperative complications showed optimal agreement between the nomogram and the actual probability.

CONCLUSIONS

Based on preoperative data, we developed a nomogram for predicting complication risks after pneumonectomy. This model may be helpful for thoracic surgeons in selecting appropriate patients for adopting prophylactic measures after surgery.

Guidelines on enhanced recovery after pulmonary lobectomy

OBJECTIVE

To establish recommendations for optimisation of the management of patients undergoing pulmonary lobectomy, particularly Enhanced Recovery After Surgery (ERAS).

DESIGN

A consensus committee of 13 experts from the French Society of Anaesthesia and Intensive Care Medicine (Soci,t, franOaise d'anesth,sie et de r,animation, SFAR) and the French Society of Thoracic and Cardiovascular Surgery (Soci,t, franOaise de chirurgie thoracique et cardiovasculaire, SFCTCV) was convened. A formal conflict-of-interest policy was developed at the onset of the process and enforced throughout. The entire guidelines process was conducted independently of any industry funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide assessment of quality of evidence.

METHODS

Five domains were defined: 1) patient pathway and patient information; 2) preoperative management and rehabilitation; 3) anaesthesia and analgesia for lobectomy; 4) surgical strategy for lobectomy; and 5) enhanced recovery after surgery. For each domain, the objective of the recommendations was to address a number of questions formulated according to the PICO model (Population, Intervention, Comparison, Outcome). An extensive literature search on these questions was carried out and analysed using the GRADE® methodology. Recommendations were formulated according to the GRADE® methodology, and were then voted by all experts according to the GRADE grid method.

RESULTS

The SFAR/SFCTCV guideline panel provided 32 recommendations on the management of patients undergoing pulmonary lobectomy. After two voting rounds and several amendments, a strong consensus was reached for 31 of the 32 recommendations and a moderate consensus was reached for the last recommendation. Seven of these recommendations present a high level of evidence (GRADE 1+), 23 have a moderate level of evidence (18 GRADE 2+ and 5 GRADE 2-), and 2 correspond to expert opinions. Finally, no recommendation was provided for 2 of the questions.

CONCLUSIONS

A strong consensus was expressed by the experts to provide recommendations to optimise the whole perioperative management of patients undergoing pulmonary lobectomy.

Perioperative fluid balance and 30-day unplanned readmission after lung cancer surgery: a retrospective study

Background

Perioperative positive fluid balance (FB) is associated with increased complications after lung resection surgery. However, its impact on the 30-day unplanned readmission rate is unclear. This study aimed to determine whether perioperative FB status during and up to 24 hours after lung resection surgery is associated with the 30-day unplanned readmission rate.

Methods

This retrospective cohort study examined adult patients aged 19 years or older who underwent lung cancer surgery at a single tertiary academic hospital between January 2005 and February 2018. Weight-based cumulative FB (%) was calculated during and up to 24 hours after surgery and was categorized as positive (≥5%), normal (0-5%), or negative (<0%). Univariable and multivariable logistic regression analyses were performed.

Results

The final analysis included 2,412 patients; 164 patients had unplanned readmission during the first 30 postoperative days (6.9%; 164/2,412). According to the multivariable logistic regression model, the positive FB group had a 2.42-time higher risk of 30-day unplanned readmission compared to the normal FB group [odds ratio (OR): 2.42; 95% confidence interval (CI): 1.20 to 4.89; P=0.014]. However, the risk of the negative FB group did not significantly differ from that of the normal FB group (OR: 1.20; 95% CI: 0.46 to 3.12; P=0.711).

Conclusions

Perioperative positive FB (>5%) during and up to 24 hours after surgery was associated with an increased 30-day unplanned readmission rate after lung cancer surgery. Future prospective studies are needed to confirm these findings.

Normalized Pulmonary Artery Diameter Predicts Occurrence of Postpneumonectomy Respiratory Failure, ARDS, and Mortality

Hypothesizing that pulmonary artery diameter is a marker of subclinical pulmonary hypertension, we assessed its impact on postoperative outcome in patients requiring pneumonectomy. Morphometric, clinical, and laboratory data were retrospectively retrieved from files of 294 consecutive patients treated by pneumonectomy for malignancy (289 NSCLC). Pulmonary artery was measured at bifurcation level on CT scan and normalized by body surface area. Median normalized pulmonary artery diameter (cut-off for analyses) was 14 mm/m2. Postoperatively, 46 patients required re-do intubation and 30 had acute respiratory distress syndrome (ARDS). Multivariate analysis showed that Charlson Comorbidity Index >5 (p = 0.0009, OR 3.8 [1.76-8.22]), right side of pneumonectomy (p = 0.013, OR 2.37 [1.20-4.71]), and higher normalized pulmonary artery diameter (p = 0.029, OR 2.16 [1.08-4.33]) were independent predictors of re-do intubation, while Charlson Comorbidity Index >5 (p = 0.018, OR 2.55 [1.17-5.59]) and higher normalized pulmonary artery diameter (p = 0.028, OR = 2.52 [1.10-5.77]) were independently associated with occurrence of ARDS. Post-operative mortality was 8.5%. Higher normalized pulmonary artery diameter, (p = 0.026, OR 3.39[1.15-9.95]), right side of pneumonectomy (p = 0.0074, OR 4.11 [1.46-11.56]), and Charlson Comorbidity Index >5 (p = 0.0011, OR 5.56 [1.99-15.54]) were independent predictors of postoperative death. We conclude that pre-operative normalized pulmonary artery diameter predicts the risk of re-do intubation, ARDS and mortality in patients undergoing pneumonectomy for cancer.

Restrictive intraoperative fluid management was associated with higher incidence of composite complications compared to less restrictive strategies in open thoracotomy: A retrospective cohort study

Restrictive fluid management has been recommended for thoracic surgery. However, specific guidelines are lacking, and there is always concern regarding impairment of renal perfusion with a restrictive policy. The objective of this study was to find the net intraoperative fluid infusion rate which shows the lowest incidence of composite complications (either pulmonary complications or acute kidney injury) in open thoracotomy. We hypothesized that a certain range of infusion rate would decrease the composite complications within postoperative 30 days. All patients (n = 1,031) who underwent open thoracotomy at a tertiary care university hospital were included in this retrospective study. The time frame of fluid monitoring was from the start of operation to postoperative 24 hours. The cutoff value of the intraoperative net fluid amount was 4–5 ml.kg⁻¹.h⁻¹ according to the minimum p-value method, thus, patients were divided into Low (≤3 ml.kg⁻¹.h⁻¹), Cutoff (4–5 ml.kg⁻¹.h⁻¹) and High (≥6 ml.kg⁻¹.h⁻¹) groups. The Cutoff group showed the lowest composite complication rate (19%, 12%, and 13% in the Low, Cutoff, and High groups, respectively, P = 0.0283; Low vs. Cutoff, P = 0.0324, Bonferroni correction). Acute respiratory distress syndrome occurred least frequently in the Cutoff group (7%, 3%, and 6% for the Low, Cutoff, and High groups, respectively, P = 0.0467; Low vs. Cutoff, P = 0.0432, Bonferroni correction). In multivariable analysis, intraoperative net fluid infusion rate was associated with composite complications, and the Cutoff group decreased risk (odds ratio 0.54, 95% confidence interval: 0.35–0.81, P = 0.0035). In conclusion, maintaining intraoperative net fluid infusion at 4–5 ml.kg⁻¹.h⁻¹ was associated with better results in open thoracotomy, in terms of composite complications, compared to more restrictive fluid management.

Balanced Chest Drainage Prevents Post-Pneumonectomy Pulmonary Oedema

BACKGROUND

Pneumonectomy in the adult patient is associated with a mortality of 1-9%. Death is often due to post pneumonectomy pulmonary oedema (PPPO). The use of balanced chest drainage system (BCD) in the setting of post pneumonectomy has been reported to be of benefit in the prevention of PPPO. This study seeks to compare the incidence of PPPO in patients who underwent pneumonectomy and whose empty pleural space was managed either with CRD or BCD.

METHODS

This retrospective observational cohort study involved 98 patients who were operated on by one surgeon at Liverpool Hospital, Sydney, Australia from 1997 to 2019. The patients were divided into two groups according to the era in which they had their pneumonectomy. Group 1 consisted of 18 patients managed with clamp-release drainage between 1997 and 2002. Group 2 consisted of 80 patients managed with balanced chest drainage between 2003 and 2019. The primary outcomes of interest were the development of PPPO and death. Demographic and clinico-pathological variables between the groups were compared including whether the phrenic nerve was sacrificed, volume of infused intraoperative fluid, duration of single lung ventilation, intraoperative tidal volumes, agents of anaesthetic induction and maintenance, mean urine output in the first 4 postoperative hours, institution of a postoperative 1.5 L fluid restriction, total chest drainage, day of chest drain removal, presence of radiological postoperative mediastinal shift, post-pneumonectomy pulmonary oedema and death. Group characteristics were compared using t-test and chi-squared for continuous and categorical variables respectively. Univariate and multivariate analysis was also undertaken using the Firth method of logistic regression for rare occurrences in a stepwise fashion.

RESULTS

Through univariate analysis, balanced chest drainage, postoperative fluid restriction and intraoperative fluid infusion showed significant effect on PPPO. Through multivariate analysis, balanced chest drainage was found to have independent protective value for PPPO and mortality.

CONCLUSION

Compared with clamp-release drainage, balanced chest drainage results in a lower incidence of post-pneumonectomy pulmonary oedema and death.

Fluid Removal With Ultrasound Guided Protocol Improves the Efficacy and Safety of Dehydration in Post-Resuscitated Critically Ill Patients: A Quasi-Experimental, Before and After Study

Fluid overload is associated with increased morbidity and mortality in critically ill patients. However, researches rarely study the precise start or end point of fluid removal and no protocol was developed to control the fluid removal process. We hypothesized that individualized fluid removal with ultrasound-guided protocol could improve the efficacy and safety of fluid removal in post-resuscitated critically ill patients. A quasi-experimental, before and after trial was conducted to identify the benefits of ultrasound-guided fluid removal. Fluid removal was performed either following the doctor's experience in Control group, or abiding the ultrasound guided protocol in Ultrasound group. The study end points were the start time, end time, length of fluid removal, and the complications related to fluid removal. A total of 85 subjects were finally analyzed in this study. The fluid removal was started earlier, completed quicker and ended earlier (21.0 ± 14.6 h vs. 35.1 ± 26.5 h, 49.8 ± 32.6 vs. 93.0 ± 42.8 h, 69.0 ± 32.2 h vs. 126.4 ± 52.5 h, P < 0.05) in Ultrasound group than in Control. The subjects had more daily negative fluid balance and urine output (-990.4 ± 636.1 mL vs. -723.6 ± 549.5 mL, 2425.8 ± 886.7 mL vs. 1560.7 ± 1125.3 mL, P < 0.05) in Ultrasound group. The time of lung B-lines to reduce to zero was shorter and B-line at the end point was less (49.5 ± 36.6 h vs. 75.6 ± 58.8 h, 0[1] vs. 0[0], P < 0.05) in Ultrasound group. The length of intensive care unit stay in shock subgroup had a tendency to shorten (96.1 ± 61.5 h vs. 174.6 ± 132.0 h, P > 0.05) in Ultrasound group. We concluded that fluid removal with individualized ultrasound-guided protocol improves the efficacy and safety of dehydration in critically ill patients.

Risk factors of postoperative acute lung injury following lobectomy for nonsmall cell lung cancer

Acute lung injury following lung resection surgery is not rare and often related to mortality. Although it has been a significant clinical and economic impact associated with increased intensive care unit (ICU) utilization, length of hospital stay, and associated cost, it is unpredictable. Aims of this study were to identify the modifiable risk factors of postoperative acute lung injury (PALI) following lung cancer surgery.We retrospectively analyzed medical records of 354 cases of lung cancer surgery in the tertiary university hospital from January 2012 to December 2015. PALI was defined as bilateral diffuse pulmonary infiltration on chest radiography, oxygenation failure (PaO2/FiO2 < 300), and absence of sign of left ventricular failure within a week from operation. We classified patients into either PALI group or non-PALI group and compared clinical characteristics of two groups. Logistic regression model was fitted to evaluate the risk factor of PALI.Among 354 cases of lung cancer surgeries, 287 lobectomies were analyzed. The overall incidence of PALI was 2.79% (8/287); four patients developed pneumonia with acute respiratory distress syndrome, and four patients developed ALI without clinical infection sign. There was no difference in baseline characteristics between PALI group and non-PALI group, but in operative parameters, a larger amount of fluid infusion was observed in PALI group. Logistic regression model showed underlying ischemic heart disease (OR 7.67, 95% CI 1.21-47.44, P = .03), interstitial lung disease (OR 30.36, 95% CI 2.30-401.52, P = .01), intravascular crystalloid fluid during surgery (OR 1.10, 95% CI 1.00-1.20, P = .04), and intraoperative transfusion (OR 56.4, 95% CI 3.53-901.39, P < .01) were risk factors of PALI. PALI increases ICU admission, use of mechanical ventilator, duration of hospital stay, and mortality.The clinical impact of PALI is marked. Significant independent risk factors have been identified in underlying ischemic heart disease, interstitial lung disease, intravascular crystalloid fluid, and transfusion during surgery.

Oesophageal Doppler guided goal-directed haemodynamic therapy in thoracic surgery - a single centre randomized parallel-arm trial

Background

Postoperative pulmonary and renal complications are frequent in patients undergoing lung surgery. Hyper- and hypovolaemia may contribute to these complications. We hypothesized that goal-directed haemodynamic management based on oesophageal Doppler monitoring would reduce postoperative pulmonary complications in a randomized clinical parallel-arm trial.

Methods

One hundred patients scheduled for thoracic surgery were randomly assigned to either standard haemodynamic management (control group) or goal-directed therapy (GDT group) guided by an oesophageal Doppler monitoring-based algorithm. The primary endpoint was postoperative pulmonary complications, including spirometry. Secondary endpoints included haemodynamic variables, renal, cardiac, and neurological complications, and length of hospital stay. The investigator assessing outcomes was blinded to group assignment.

Results

Forty-eight subjects of each group were analysed. Compared to the control group, fewer subjects in the GDT group developed postoperative pulmonary complications (6 vs. 15 patients; P  = 0.047), while spirometry did not differ between groups. Compared to the control group, patients of the GDT group showed higher cardiac index (2.9 vs. 2.1 [l min - 1 m  - 2 ]; P  < 0.001) and stroke volume index (43 vs. 34 [ml m 2 ]; P  < 0.001) during surgery. Renal, cardiac and neurological complications did not differ between groups. Length of hospital stay was shorter in the GDT compared to the control group (9 vs. 11 days; P  = 0.005).

Conclusions

Compared to standard haemodynamic management, oesophageal Doppler monitor-guided GDT was associated with fewer postoperative pulmonary complications and a shorter hospital stay.

Clinical trial registration.

The study was registered in the German Clinical Trials Register (DRKS 00006961). https://drks-neu.uniklinik-freiburg.de/drks_web/.

The Right Ventricle During Selective Lung Ventilation for Thoracic Surgery

The right ventricle (RV) has been an area of evolving interest after decades of being ignored and considered less important than the left ventricle. Right ventricular dysfunction/failure is an independent predictor of mortality and morbidity in cardiac surgery; however, very little is known about the incidence or impact of RV dysfunction/failure in thoracic surgery. The pathophysiology of RV dysfunction/failure has been studied in the context of acute respiratory distress syndrome (ARDS), cardiac surgery, pulmonary hypertension, and left ventricular failure, but limited data exist in literature addressing the issue of RV dysfunction/failure in the context of thoracic surgery and one-lung ventilation (OLV). Thoracic surgery and OLV present as a unique situation where the RV is faced with sudden changes in afterload, preload, and contractility throughout the perioperative period. The authors discuss the possible pathophysiologic mechanisms that can affect adversely the RV during OLV and introduce the term RV injury to the myocardium that is affected adversely by the various intraoperative factors, which then makes it predisposed to acute dysfunction. The most important of these mechanisms seems to be the role of intraoperative mechanical ventilation, which potentially could cause both ventilator-induced lung injury leading to ARDS and RV injury. Identification of at-risk patients in the perioperative period using focused imaging, particularly echocardiography, is paramount. The authors also discuss the various RV-protective strategies required to prevent RV dysfunction and management of established RV failure.

Patients experiencing early acute respiratory failure have high postoperative mortality after pneumonectomy

OBJECTIVE

Post-pneumonectomy acute respiratory failure leading to invasive mechanical ventilation carries a severe prognosis especially when acute respiratory distress syndrome occurs. The aim of this study was to describe risk factors and outcome of acute respiratory failure.

METHODS

We retrospectively reviewed clinical files of all patients who underwent pneumonectomy in a single center between 2005 and 2015. Risk factors and outcome of acute respiratory failure were assessed in univariate and multivariate analysis.

RESULTS

Among the 543 patients who underwent pneumonectomy in the period of study, 89 (16.4%) needed reintubation within the 30th postoperative day and 60 of these (11% of all pneumonectomies) developed acute respiratory distress syndrome. In multivariate analysis, right-side of pneumonectomy (odds ratio [OR], 2.29; 95% confidence interval [CI], 1.24-4.22), chronic cardiac disease (OR, 2.15; 95% CI, 1.08-4.25), Charlson Comorbidity Index (OR, 1.35; 95% CI, 1.14-1.61), carinal resection (OR, 3.23; 95% CI, 1.26-8.29), and extrapleural pneumonectomy (OR, 8.36; 95% CI, 3.31-21.11) were identified as independent risk factors of reintubation. Thirty-day mortality was 7.7% for all pneumonectomies, 41.6% (37/89) in the invasive ventilation group, and 53.3% (32/60) in patients with acute respiratory distress syndrome. In non-reintubated patients, 30-day mortality was 1.1% (5/454). In reintubated patients, 5-year survival was 27.1% (95% CI, 17.8-41.4).

CONCLUSIONS

Early acute respiratory failure requiring reintubation remains a severe complication of pneumonectomy with a poor outcome.

Pneumonectomy for Non-Small Cell Lung Cancer

Lung cancer is the leading cause of cancer deaths and its incidence continues to increase. Emerging therapies as part of a multimodal approach are making more patients eligible for surgical resection. As more surgeons are treating locally advanced non-small cell lung cancer they find themselves recommending pneumonectomy as the surgical component of the multidisciplinary plan. Performing a pneumonectomy is technically demanding and is associated with many potential perioperative comorbidities. With the proper preparation, experience, and attention to perioperative care, pneumonectomy can be carried out safely with excellent outcomes and a good quality of life.

Intensive care in thoracic oncology

The admission of lung cancer patients to intensive care is related to postprocedural/postoperative care and medical complications due to cancer or its treatment, but is also related to acute organ failure not directly related to cancer.

Despite careful preoperative risk management and the use of modern surgical and anaesthetic techniques, thoracic surgery remains associated with high morbidity, related to the extent of resection and specific comorbidities. Fast-tracking processes with timely recognition and treatment of complications favourably influence patient outcome. Postoperative preventive and therapeutic management has to be carefully planned in order to reduce postoperative morbidity and mortality.

For patients with severe complications, intensive care unit (ICU) mortality rate ranges from 13% to 47%, and hospital mortality ranges from 24% to 65%. Common predictors of in-hospital mortality are severity scores, number of failing organs, general condition, respiratory distress and the need for mechanical ventilation or vasopressors. When considering long-term survival after discharge, cancer-related parameters retain their prognostic value.

Thoracic surgeons, anesthesiologists, pneumologists, intensivists and oncologists need to develop close and confident partnerships aimed at implementing evidence-based patient care, securing clinical pathways for patient management while promoting education, research and innovation. The final decision on admitting a patient with lung to the ICU should be taken in close partnership between this medical team and the patient and his or her relatives.

[State of the art in fluid and volume therapy : A user-friendly staged concept]

Adequate fluid therapy is highly important for the perioperative outcome of our patients. Both, hypovolemia and hypervolemia can lead to an increase in perioperative complications and can impair the outcome. Therefore, perioperative infusion therapy should be target-oriented. The main target is to maintain the patient's preoperative normovolemia by using a sophisticated, rational infusion strategy.Perioperative fluid losses should be discriminated from volume losses (surgical blood loss or interstitial volume losses containing protein). Fluid losses as urine or perspiratio insensibilis (0.5-1.0 ml/kg/h) should be replaced by balanced crystalloids in a ratio of 1:1. Volume therapy step 1: Blood loss up to a maximum value of 20% of the patient's blood volume should be replaced by balanced crystalloids in a ratio of 4(-5):1. Volume therapy step 2: Higher blood losses should be treated by using iso-oncotic, preferential balanced colloids in a ratio of 1:1. For this purpose hydroxyethyl starch can also be used perioperatively if there is no respective contraindication, such as sepsis, burn injuries, critically ill patients, renal impairment or renal replacement therapy, and severe coagulopathy. Volume therapy step 3: If there is an indication for red cell concentrates or coagulation factors, a differentiated application of blood and blood products should be performed.

Initial 12-h operative fluid volume is an independent risk factor for pleural effusion after hepatectomy

Pleural effusion after hepatectomy is associated with significant morbidity and prolonged hospital stays. Several studies have addressed the risk factors for postoperative pleural effusion. However, there are no researches concerning the role of the initial 12-h operative fluid volume. The aim of this study was to evaluate whether the initial 12-h operative fluid volume during liver resection is an independent risk factor for pleural effusion after hepatectomy. In this study, we retrospectively analyzed clinical data of 470 patients consecutively undergoing elective hepatectomy between January 2011 and December 2012. We prospectively collected and retrospectively analyzed baseline and clinical data, including preoperative, intraoperative, and postoperative variables. Univariate and multivariate analyses were carried out to identify whether the initial 12-h operative fluid volume was an independent risk factor for pleural effusion after hepatectomy. The multivariate analysis identified 2 independent risk factors for pleural effusion: operative time [odds ratio (OR)=10.2] and initial 12-h operative fluid volume (OR=1.0003). Threshold effect analyses revealed that the initial 12 h operative fluid volume was positively correlated with the incidence of pleural effusion when the initial 12-h operative fluid volume exceeded 4636 mL. We conclude that the initial 12-h operative fluid volume during liver resection and operative time are independent risk factors for pleural effusion after hepatectomy. Perioperative intravenous fluids should be restricted properly.

Diagnosis Accuracy of Mean Arterial Pressure Variation during a Lung Recruitment Maneuver to Predict Fluid Responsiveness in Thoracic Surgery with One-Lung Ventilation

Background. Lung recruitment maneuver (LRM) during thoracic surgery can reduce systemic venous return and resulting drop in systemic blood pressure depends on the patient's fluid status. We hypothesized that changes in systemic blood pressure during the transition in LRM from one-lung ventilation (OLV) to two-lung ventilation (TLV) may provide an index to predict fluid responsiveness. Methods. Hemodynamic parameters were measured before LRM (T0); after LRM at the time of the lowest mean arterial blood pressure (MAP) (T1) and at 3 minutes (T2); before fluid administration (T3); and 5 minutes after ending it (T4). If the stroke volume index increased by >25% following 10 mL/kg colloid administration for 30 minutes, then the patients were assigned to responder group. Results. Changes in MAP, central venous pressure (CVP), and stroke volume variation (SVV) between T0 and T1 were significantly larger in responders. Areas under the curve for change in MAP, CVP, and SVV were 0.852, 0.759, and 0.820, respectively; the optimal threshold values for distinguishment of responders were 9.5 mmHg, 0.5 mmHg, and 3.5%, respectively. Conclusions. The change in the MAP associated with LRM at the OLV to TLV conversion appears to be a useful indicator of fluid responsiveness after thoracic surgery. Trial Registration. This trial is registered at Clinical Research Information Service with KCT0000774.

Lung Injury After One-Lung Ventilation: A Review of the Pathophysiologic Mechanisms Affecting the Ventilated and the Collapsed Lung

Lung injury is the leading cause of death after thoracic surgery. Initially recognized after pneumonectomy, it has since been described after any period of 1-lung ventilation (OLV), even in the absence of lung resection. Overhydration and high tidal volumes were thought to be responsible at various points; however, it is now recognized that the pathophysiology is more complex and multifactorial. All causative mechanisms known to trigger ventilator-induced lung injury have been described in the OLV setting. The ventilated lung is exposed to high strain secondary to large, nonphysiologic tidal volumes and loss of the normal functional residual capacity. In addition, the ventilated lung experiences oxidative stress, as well as capillary shear stress because of hyperperfusion. Surgical manipulation and/or resection of the collapsed lung may induce lung injury. Re-expansion of the collapsed lung at the conclusion of OLV invariably induces duration-dependent, ischemia-reperfusion injury. Inflammatory cytokines are released in response to localized injury and may promote local and contralateral lung injury. Protective ventilation and volatile anesthesia lessen the degree of injury; however, increases in biochemical and histologic markers of lung injury appear unavoidable. The endothelial glycocalyx may represent a common pathway for lung injury creation during OLV, because it is damaged by most of the recognized lung injurious mechanisms. Experimental therapies to stabilize the endothelial glycocalyx may afford the ability to reduce lung injury in the future. In the interim, protective ventilation with tidal volumes of 4 to 5 mL/kg predicted body weight, positive end-expiratory pressure of 5 to 10 cm H2O, and routine lung recruitment should be used during OLV in an attempt to minimize harmful lung stress and strain. Additional strategies to reduce lung injury include routine volatile anesthesia and efforts to minimize OLV duration and hyperoxia.

Focus on treatment complications and optimal management surgery

Thoracic surgery comprises major procedures which may be challenging, not only from a technical point of view but also regarding anesthetic and postoperative management. Complications are common occurrences which are also related to the comorbidity of the patients. After major lung resections pulmonary and pleural complications are often encountered. In this overview more surgically related complications are discussed, focusing on postpneumonectomy pulmonary edema, thromboembolic disease including pulmonary embolism, prolonged air leak, lobar torsion, persistent pleural space, empyema and bronchopleural fistula. Prevention, timely recognition, and early adequate treatment are key points as complications initially considered to be minor, may suddenly turn into life-threatening events. To this end multidisciplinary cooperation is necessary. Preoperative smoking cessation, adequate pain control, attention to nutritional status, incentive spirometry and early mobilization are important factors to reduce the incidence of postoperative complications.

Preoperative pulmonary vascular morphology and its relationship to postpneumonectomy hemodynamics

RATIONALE AND OBJECTIVES

Pulmonary edema and pulmonary hypertension are postsurgical complications of pneumonectomy that may represent the remaining pulmonary vasculature's inability to accommodate the entirety of the cardiac output. Quantification of the aggregate pulmonary vascular cross-sectional area (CSA) has been used to study the development of pulmonary vascular disease in smokers. In this study, we applied this technique to demonstrate the potential utility of pulmonary vascular quantification in surgical risk assessment. Our hypothesis was that those subjects with the lowest aggregate vascular CSA in the nonoperative lung would be most likely to have elevated pulmonary vascular pressures in the postoperative period.

MATERIALS AND METHODS

A total of 61 subjects with postoperative hemodynamics and adequate imaging were identified from 159 patients undergoing pneumonectomies for mesothelioma. The total CSA of blood vessels perpendicular to the plane of computed tomographic (CT) scan slices was computed for blood vessels <5 mm(2) (CSA 5 mm). This measurement expressed as a percentage of lung parenchyma area (CSA 5%) was compared to postoperative hemodynamic measurements obtained by right heart catheterization.

RESULTS

In patients where a contrasted CT scan was used (n = 26), CSA 5% was correlated with postoperative day 0 minimum cardiac index (R = 0.37, P = .03) but not with the maximum pulmonary arterial pressures. In patients with noncontrast CT scans (n = 35), CSA 5% was inversely correlated with postoperative day 0 maximum pulmonary arterial pressures (R = 0.43, P = .03) but not with the minimum cardiac index. The preoperative perfusion fraction of the nonsurgical lung did not correlate with postoperative hemodynamics.

CONCLUSIONS

CSA of pulmonary vasculature with an area ≤5 mm(2) has potential in estimating the ability of pulmonary vascular bed to accommodate postsurgical changes in pneumonectomy.

Special article: the endothelial glycocalyx: emerging concepts in pulmonary edema and acute lung injury

The endothelial glycocalyx is a dynamic layer of macromolecules at the luminal surface of vascular endothelium that is involved in fluid homeostasis and regulation. Its role in vascular permeability and edema formation is emerging but is still not well understood. In this special article, we highlight key concepts of endothelial dysfunction with regards to the glycocalyx and provide new insights into the glycocalyx as a mediator of processes central to the development of pulmonary edema and lung injury.

Incidence and risk factors for acute lung injury after open thoracotomy for thoracic diseases

BACKGROUND

Acute lung injury (ALI) is a major cause of morbidity and mortality after open thoracotomy. The purpose of the study was to identify the incidence and risk factors for ALI so as to prevent its occurrence and improve surgical results.

METHODS

A prospective controlled study was carried out in 364 patients undergone open thoracotomy. Fifty-eight high risk elderly patients and 56 young patients as matched controls were prospectively entered into the study. The two groups were compared to identify the possible risk factors for ALI.

RESULTS

ALI occurred exclusively in elderly patients, accounted for 2.7% of the whole series (10/364) and 7.9% of elderly patients (10/127). The mortality for patients with ALI was 30%, significantly higher than those without (1.0%, P=0.001). Upon univariate analysis, increased age, obesity, chronic obstructive pulmonary disease (COPD), poor spirometry, and positive fluid balance on postoperative day 1 were associated with increased risk of developing ALI. Upon multivariate analysis, only poor spirometry and excessive positive fluid balance on postoperative day 1 were revealed as independent risk factors for ALI.

CONCLUSIONS

ALI after open thoracotomy has a high mortality. COPD and excessive positive fluid balance on the first postoperative day are significant predictors, suggesting stringent patient selection and timely conservative fluid management may be helpful in reducing this extremely devastating complication.

Acute respiratory distress syndrome after pulmonary resection

Postoperative acute respiratory distress syndrome (ARDS) is a recognized complication of pulmonary resection. It is characterized by the acute onset of hypoxemia with radiographic infiltrates consistent with pulmonary edema, without elevations in the pulmonary capillary wedge pressure. Many studies suggest that around 2-5 % of patients develop some degree of lung injury, and the mortality from ARDS following pulmonary resection remains high. ARDS following thoracotomy and lung resection has a miserable prognosis, with overall hospital mortality rates over 25 %. The present review evaluates the evidence available in the literature tracking perioperative mortality and morbidity as well as the pathogenesis and management of ARDS in patients undergoing pulmonary resection.

Perioperative fluid management for pulmonary resection surgery and esophagectomy

Perioperative fluid management is of significant importance during pulmonary resection surgery and esophagectomy. Excessive fluid administration has been consistently shown as a risk factor for lung injury after thoracic procedures. Probable causes of this serious complication include fluid overload, lung lymphatics and pulmonary endothelial damage. Along with new insights regarding the Starling equation and the absence of a third space, current evidence supports a restrictive fluid regimen for patients undergoing pulmonary resection surgery and esophagectomy. Multiple minimally invasive hemodyamic monitoring devices, including pulse pressure/stroke volume variation, esophageal Doppler, and extravascular lung water measurement, were evaluated for optimizing perioperative fluid therapy. Further research regarding the prevention, diagnosis, and treatment of acute lung injury after pulmonary resection and esophagectomy is required.

Are non-cardiac surgeries safe for dialysis patients? - A population-based retrospective cohort study

BACKGROUND

End-stage renal disease represents a risk complex that complicates surgical results. The surgical outcomes of dialysis patients have been studied in specific fields, but the global features of postoperative adverse outcomes in dialysis patients receiving non-cardiac surgeries have not been examined.

METHODS

Taiwan's National Health Insurance Research Database was used to study 8,937 patients under regular dialysis with 8,937 propensity-score matched-pair controls receiving non-cardiac surgery between 2004 and 2007. We investigated the influence of hemodialysis and peritoneal dialysis, effects of hypertension and diabetes, and impact of additional comorbidities on postoperative adverse outcomes.

RESULTS

Postoperative mortality in dialysis patients was higher than in controls (odds ratio [OR] 3.33, 95% confidence interval [CI] 2.56 to 4.33) when receiving non-cardiac surgeries. Complications such as acute myocardial infarction, pneumonia, bleeding, and septicemia were significantly increased. Postoperative mortality was significantly increased among peritoneal dialysis patients (OR 2.71, 95% CI 1.70 to 4.31) and hemodialysis patients (OR 3.42, 95% CI 2.62 to 4.47) than in controls. Dialysis patients with both hypertension and diabetes had the highest risk of postoperative complications; these risks increased with number of preoperative medical conditions. Patients under dialysis also showed significantly increased length of hospitalization, more ICU stays and higher medical expenditures.

CONCLUSION

Surgical patients under dialysis encountered significantly higher postoperative complications and mortality than controls when receiving non-cardiac surgeries. Different dialysis techniques, pre-existing hypertension/diabetes, and various comorbidities had complication-specific impacts on surgical adverse outcomes. These findings can help surgical teams provide better risk assessment and postoperative care for dialysis patients.

Does a conservative fluid management strategy in the perioperative management of lung resection patients reduce the risk of acute lung injury?

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was whether a conservative fluid management strategy in the perioperative management of lung resection patients is associated with a reduced incidence of postoperative acute lung injury (PALI) and/or acute respiratory distress syndrome (ARDS) in the recovery period. Sixty-seven papers were found using the reported search, of which 13 level III and 1 level IV evidence studies represented the best evidence to answer the question. Two retrospective case-control studies demonstrated a direct association between liberal fluid intake and the incidence of PALI/ARDS following lung resection on multivariate analysis (MVA) with odds ratios (ORs) of 1.42 (95% CI 1.09-4.32, P = 0.011) and 2.91 (1.9-7.4, P = 0.001). In non-PALI/ARDS cases, the mean intraoperative fluid infusion volume was significantly less [1.22 l (1.17-1.26) vs 1.68 l (1.46-1.9) P = 0.005], the fluid balance over the first 24 postoperative hours was significantly less [1.52 l positive (1.44-1.60) vs 2.0 l positive (1.6-2.4) P = 0.026] and cumulated intra- and postoperative fluid infusion was significantly less [2.0 ml/kg/h (1.7-2.3) vs 2.6 ml/kg/h (2.3-2.9) P = 0.003]. These data show that the difference between fluid regimes associated with an increased incidence of PALI/ARDS (i.e. 'liberal') and those which are not (i.e. 'conservative') is narrow but significant. However, this does not prove a causative role for liberal fluid in the multifactorial development of PALI/ARDS. On this best evidence, we recommend intra- and postoperative maintenance fluid to be administered at 1-2 ml/kg/h and that a positive fluid balance of 1.5 l should not be exceeded in the perioperative period with caution being exercised with regard to the adequacy of oxygen delivery. If the fluid balance exceeds this threshold, a high index of suspicion for PALI/ARDS should be adopted and escalation of the level of care should be considered. If a patient develops signs of hypoperfusion after these thresholds are exceeded, inotropic/vasopressor support should be considered.

Intraoperative fluid therapy and pulmonary complications

The purpose of this study was to evaluate the effects of intraoperative fluid therapy on length of hospital stay and pulmonary complications in patients undergoing spine surgery. A total of 1307 patients were analyzed. Sixteen pulmonary complications were observed. Patients with a higher volume of administered crystalloids, colloids, and total intravenous fluids were more likely to have postoperative respiratory complications: the odds of postoperative respiratory complications increased by 30% with an increase of 1000 mL of crystalloid administered. The best cutoff point for total fluids was 4165 mL, with a sensitivity of 0.8125 and specificity of 0.7171, for postoperative pulmonary complications. A direct correlation existed between fluids and length of stay: patients who received >4165 mL of total fluids had an average length of stay of 3.88±4.66 days vs 2.3±3.9 days for patients who received <4165 mL of total fluids (P<.0001). This study should be considered as hypothesis-generating to design a prospective trial comparing high vs low intraoperative fluid regiments for patients undergoing spine surgery.

Effect of methylprednisolone on perivascular pulmonary edema, inflammatory infiltrate, VEGF and TGF-beta immunoexpression in the remaining lungs of rats after left pneumonectomy

Pneumonectomy is associated with high rates of morbimortality, with postpneumonectomy pulmonary edema being one of the leading causes. An intrinsic inflammatory process following the operation has been considered in its physiopathology. The use of corticosteroids is related to prevention of this edema, but no experimental data are available to support this hypothesis. We evaluated the effect of methylprednisolone on the remaining lungs of rats submitted to left pneumonectomy concerning edema and inflammatory markers. Forty male Wistar rats weighing 300 g underwent left pneumonectomy and were randomized to receive corticosteroids or not. Methylprednisolone at a dose of 10 mg/kg was given before the surgery. After recovery, the animals were sacrificed at 48 and 72 h, when the pO(2)/FiO(2) ratio was determined. Right lung perivascular edema was measured by the index between perivascular and vascular area and neutrophil density by manual count. Tissue expression of vascular endothelial growth factor (VEGF) and transforming growth factor-beta (TGF-β) were evaluated by immunohistochemistry light microscopy. There was perivascular edema formation after 72 h in both groups (P = 0.0031). No difference was observed between operated animals that received corticosteroids and those that did not concerning the pO(2)/FiO(2) ratio, neutrophil density or TGF-β expression. The tissue expression of VEGF was elevated in the animals that received methylprednisolone both 48 and 72 h after surgery (P = 0.0243). Methylprednisolone was unable to enhance gas exchange and avoid an inflammatory infiltrate and TGF-β expression also showed that the inflammatory process was not correlated with pulmonary edema formation. However, the overexpression of VEGF in this group showed that methylprednisolone is related to this elevation.

Postresectional lung injury in thoracic surgery pre and intraoperative risk factors: a retrospective clinical study of a hundred forty-three cases

Introduction

Acute respiratory dysfunction syndrome (ARDS), defined as acute hypoxemia accompanied by radiographic pulmonary infiltrates without a clearly identifiable cause, is a major cause of morbidity and mortality after pulmonary resection. The aim of the study was to determine the pre and intraoperative factors associated with ARDS after pulmonary resection retrospectively.

Methods

Patients undergoing elective pulmonary resection at Adnan Menderes University Medical Faculty Thoracic Surgery Department from January 2005 to February 2010 were included in this retrospective study. The authors collected data on demographics, relevant co-morbidities, the American Society of Anesthesiologists (ASA) Physical Status classification score, pulmonary function tests, type of operation, duration of surgery and intraoperative fluid administration (fluid therapy and blood products). The primary outcome measure was postoperative ARDS, defined as the need for continuation of mechanical ventilation for greater than 48-hours postoperatively or the need for reinstitution of mechanical ventilation after extubation. Statistical analysis was performed with Fisher exact test for categorical variables and logistic regression analysis for continuous variables.

Results

Of one hundred forty-three pulmonary resection patients, 11 (7.5%) developed postoperative ARDS. Alcohol abuse (p = 0.01, OR = 39.6), ASA score (p = 0.001, OR: 1257.3), resection type (p = 0.032, OR = 28.6) and fresh frozen plasma (FFP)(p = 0.027, OR = 1.4) were the factors found to be statistically significant.

Conclusion

In the light of the current study, lung injury after lung resection has a high mortality. Preoperative and postoperative risk factor were significant predictors of postoperative lung injury.

Effects of pneumonectomy on nitric oxide synthase expression and perivascular edema in the remaining lung of rats

Pneumonectomy is associated with high mortality and high rates of complications. Postpneumonectomy pulmonary edema is one of the leading causes of mortality. Little is known about its etiologic factors and its association with the inflammatory process. The purpose of the present study was to evaluate the role of pneumonectomy as a cause of pulmonary edema and its association with gas exchange, inflammation, nitric oxide synthase (NOS) expression and vasoconstriction. Forty-two non-specific pathogen-free Wistar rats were included in the study. Eleven animals died during or after the procedure, 21 were submitted to left pneumonectomy and 10 to sham operation. These animals were sacrificed after 48 or 72 h. Perivascular pulmonary edema was more intense in pneumonectomized rats at 72 h (P = 0.0131). Neutrophil density was lower after pneumonectomy in both groups (P = 0.0168). There was higher immunohistochemical expression of eNOS in the pneumonectomy group (P = 0.0208), but no statistically significant difference in the expression of iNOS. The lumen-wall ratio and pO(2)/FiO(2) ratio did not differ between the operated and sham groups after pneumonectomy. Left pneumonectomy caused perivascular pulmonary edema with no elevation of immunohistochemical expression of iNOS or neutrophil density, suggesting the absence of correlation with the inflammatory process or oxidative stress. The increased expression of eNOS may suggest an intrinsic production of NO without signs of vascular reactivity.

Pathological finding of subclinical interstitial pneumonia as a predictor of postoperative acute respiratory distress syndrome after pulmonary resection

OBJECTIVE

Post-surgical interstitial pneumonia (IP) is a part of postoperative acute respiratory distress syndrome (ARDS). Some cases of ARDS may be an acute exacerbation of idiopathic pulmonary fibrosis (IPF) that is generally not recognised as IPF prior to surgery. In this study, we evaluated IP on preoperative computed tomography (CT) and histopathological findings in patients who underwent thoracic surgery, and attempted to identify high-risk patients who might develop postoperative ARDS.

METHODS

A retrospective review of preoperative CT and histopathological examination was performed in 487 patients who underwent lobectomy for primary lung cancer at our institute.

RESULTS

The incidence of ARDS was 2.05%, and histopathological finding of IP was the only predictor of ARDS (P = 0.038, odds ratio (OR) = 6.89). The incidence of IP on histopathological examination was 9.7% for all cases of lung cancer; and the incidence of ARDS in the IP-positive group (31.8%) was significantly different from that in the IP-negative group (1.5%) (P<0.05). However, in 85.7% of patients with ARDS, who were histologically IP-positive, IP was masked by emphysematous findings and thus not detected on preoperative CT.

CONCLUSIONS

In this study, histopathological finding of IP was the only predictor of ARDS; however, it was difficult to identify preoperatively because emphysematous change was also present in the majority of cases, which masks the findings of IP on CT. If identification of the high-risk case of ARDS is insisted upon, screening the presence or absence of IP (e.g., just in the patients with emphysema or IP finding on CT) by histopathological examination, as the need arises, after surgery using resected lung might be one of the additional methods of identifying those at high risk of ARDS.

Anesthetic considerations in 65 patients undergoing unilateral pneumonectomy: problems related to fluid therapy and hemodynamic control

STUDY OBJECTIVE

To examine perioperative management and complications in patients undergoing pneumonectomy.

DESIGN

Observational cohort study.

SETTING

University-affiliated city hospital.

MEASUREMENTS

65 patients who underwent unilateral pneumonectomy for resection of lung cancer between March 1997 and October 2007 were included in this study. Patients who underwent pneumonectomy were then classified into two groups: Group C patients had signs of postoperative acute right heart failure, and Group N patients had no signs of postoperative acute right heart failure.

MAIN RESULTS

In the pneumonectomy patients, extubation did not occur in 8 patients (12%) and postoperative death occurred in 4 patients (6%), compared with no such occurrences among patients who underwent lobectomy. Perioperative respiratory function was significantly lower in Group C (P < 0.05) than Group N. Fluid infusion volume, fluid balance volume, intraoperative total fluid balance, urine output volume, blood loss volume, blood transfusion volume, times of administration of vasopressors intraoperatively, and number of patients requiring intraoperative administration of catecholamines were significantly greater in Group C (P < 0.05) than Group N.

CONCLUSIONS

Fluid infusion volume, fluid balance volume, intraoperative total balance, blood loss volume, and blood transfusion volume were important intraoperative risk factors in the development of postoperative right-sided heart failure.

Risk factor analysis for postoperative acute respiratory distress syndrome and early mortality after pneumonectomy: the predictive value of preoperative lung perfusion distribution

OBJECTIVES

This study aims to establish the preoperative risk factors in the development of acute respiratory distress syndrome (ARDS) and early mortality after pneumonectomy for lung cancer and to examine the influence of reduced pulmonary perfusion on outcomes.

METHODS

Between 1994 and 2009, of 425 patients who underwent simple pneumonectomy for primary lung cancer, 164 who were preoperatively evaluated with lung perfusion scanning formed the population of this study.

RESULTS

Of 30 (18.3%) patients who had major pulmonary complications, 17 (10.4%) progressed to ARDS, 15 of whom subsequently died. On multivariable logistic regression analyses, lower predicted postoperative forced expiratory volume in 1 second (ppo-FEV(1); relative risk of 0.93 [P = .020] for ARDS and 0.94 [P = .027] for mortality) and greater perfusion fraction of resected lung (relative risk of 1.10 [P = .003] for ARDS and 1.09 [P = .002] for mortality) were found to be independent factors associated with ARDS and early mortality. With a cut-off value of 35% for perfusion fraction of resected lung, patients with a perfusion fraction of greater than 35% had a greater incidence of ARDS (17.3% vs 3.3%, P = .005) and early mortality (19.8% vs 6.0%, P = .010) than those with a perfusion fraction of 35% or less.

CONCLUSIONS

Patients with a low ppo-FEV(1), a high perfusion fraction of resected lung, or both had a higher incidence of ARDS and early mortality after pneumonectomy. Therefore, although the ppo-FEV(1) appears to be within an acceptable limit for pneumonectomy, much attention should be given to patients with a high perfusion fraction of resected lung.

Acute lung injury after thoracic surgery

In this review, the authors discussed criteria for diagnosing ALI; incidence, etiology, preoperative risk factors, intraoperative management, risk-reduction strategies, treatment, and prognosis. The anesthesiologist needs to maintain an index of suspicion for ALI in the perioperative period of thoracic surgery, particularly after lung resection on the right side. Acute hypoxemia, imaging analysis for diffuse infiltrates, and detecting a noncardiogenic origin for pulmonary edema are important hallmarks of acute lung injury. Conservative intraoperative fluid administration of neutral to slightly negative fluid balance over the postoperative first week can reduce the number of ventilator days. Fluid management may be optimized with the assistance of new imaging techniques, and the anesthesiologist should monitor for transfusion-related lung injuries. Small tidal volumes of 6 mL/kg and low plateau pressures of < or =30 cmH2O may reduce organ and systemic failure. PEEP may improve oxygenation and increases organ failure-free days but has not shown a mortality benefit. The optimal mode of ventilation has not been shown in perioperative studies. Permissive hypercapnia may be needed in order to reduce lung injury from positive-pressure ventilation. NO is not recommended as a treatment. Strategies such as bronchodilation, smoking cessation, steroids, and recruitment maneuvers are unproven to benefit mortality although symptomatically they often have been shown to help ALI patients. Further studies to isolate biomarkers active in the acute setting of lung injury and pharmacologic agents to inhibit inflammatory intermediates may help improve management of this complex disease.

[Perioperative fluid management: an analysis of the present situation]

Optimal perioperative fluid management is still controversial. Besides well known perioperative hypovolaemia, hypervolaemia has an influence on perioperative morbidity and mortality, particularly with regard to the patient's medical history, a reduced cardiac and pulmonal function and the operation itself. The concepts of preoperative, intraoperative and postoperative fluid administration are neither adequately validated, nor sufficiently integrated into a perioperative concept. At the present, moderate fluid administration to improve preoperative and postoperative outcome is safe in minor or medium surgical procedures. High-risk surgical patients benefit from a time-oriented or/and goal-oriented monitored fluid therapy. In the past only little attention has been concentrated on postoperative fluid management, but may be stimulated by the new concepts of fast track surgery.