Right ventricular function during and after thoracic surgery.

PURPOSE OF REVIEW: Right ventricular (RV) dysfunction following thoracotomy and pulmonary resection is a known phenomenon but questions remain about its mechanism, risk factors, and clinical significance. Acute RV dysfunction can present intraoperatively and postoperatively, persisting for 2 months after surgery. RECENT FINDINGS: Recently, the pulmonology literature has emphasized pulmonary arterial capacitance, rather than pulmonary vascular resistance, as a marker to predict disease progression and outcome in patients with pulmonary hypertension and heart failure. Diagnostic focus has emerged on the use of cardiac MRI and new echocardiographic parameters to better quantify the presence of RV dysfunction and the role of pulmonary capacitance in its development. SUMMARY: In this review, we examine the most recent literature on RV dysfunction following lung resection, including possible mechanisms, time span of RV dysfunction, and available diagnostic modalities. The clinical relevance of these factors on preoperative assessment and risk stratification are presented.

Extravascular lung water monitoring for thoracic and lung transplant surgeries.

PURPOSE OF REVIEW: Excessive accumulation of extravascular lung water (EVLW) resulting in pulmonary edema is the most feared complication following thoracic surgery and lung transplant. ICUs have long relied on chest radiography to monitor pulmonary status postoperatively but the increasing recognition of the limitations of bedside plain films has fueled development of newer technologies, which offer earlier detection, quantitative assessments, and can aide in preoperative screening of surgical candidates. In this review, we focus on the emergence of transpulmonary thermodilution (TPTD) and lung ultrasound with a focus on the clinical integration of these modalities into current intraoperative and critical care practices. RECENT FINDINGS: Recent studies demonstrate transpulmonary thermodilution and lung ultrasound provide greater sensitivity and earlier detection of lung water accumulation and are useful to guide clinical management. Assessments from these techniques have predictive value of postoperative outcome. Further, EVLW assessment shows promise as a preoperative screening tool in lung transplant patients. SUMMARY: Monitoring EVLW in the perioperative period offers clinicians a powerful tool to guide fluid therapy and manage pulmonary edema. Both TPTD and lung ultrasound have unique attributes in the care of thoracic surgery and lung transplant patients.

Assessment of Pulmonary Edema: Principles and Practice.

Pulmonary edema increasingly is recognized as a perioperative complication affecting outcome. Several risk factors have been identified, including those of cardiogenic origin, such as heart failure or excessive fluid administration, and those related to increased pulmonary capillary permeability secondary to inflammatory mediators. Effective treatment requires prompt diagnosis and early intervention. Consequently, over the past 2 centuries a concentrated effort to develop clinical tools to rapidly diagnose pulmonary edema and track response to treatment has occurred. The ideal properties of such a tool would include high sensitivity and specificity, easy availability, and the ability to diagnose early accumulation of lung water before the development of the full clinical presentation. In addition, clinicians highly value the ability to precisely quantify extravascular lung water accumulation and differentiate hydrostatic from high permeability etiologies of pulmonary edema. In this review, advances in understanding the physiology of extravascular lung water accumulation in health and in disease and the various mechanisms that protect against the development of pulmonary edema under physiologic conditions are discussed. In addition, the various bedside modalities available to diagnose early accumulation of extravascular lung water and pulmonary edema, including chest auscultation, chest roentgenography, lung ultrasonography, and transpulmonary thermodilution, are examined. Furthermore, advantages and limitations of these methods for the operating room and intensive care unit that are critical for proper modality selection in each individual case are explored.

Transpulmonary Thermodilution: Its Role in Assessment of Lung Water and Pulmonary Edema.

Tissue edema, in particular pulmonary edema, increasingly is recognized as a perioperative complication affecting outcome. Management strategies directed at avoiding excessive fluid administration, reducing inflammatory response, and decreasing capillary permeability commonly are advocated in perioperative care protocols. In this review, transpulmonary thermodilution (TPTD) as a bedside tool to quantitatively monitor lung water accumulation and optimize fluid therapy is examined. Furthermore, the roles of TPTD as an early detector of fluid accumulation before the development of overt pulmonary edema and in risk stratification are explored. In addition, the ability of TPTD to provide insight into the etiology of pulmonary edema, specifically differentiating hydrostatic versus increased pulmonary capillary permeability, is emerging as an aid in therapeutic decision-making. The combination of hemodynamic and lung water data afforded by TPTD offers unique benefits for the care of high-risk perioperative patients.

Extravascular Lung Water and Tissue Perfusion Biomarkers After Lung Resection Surgery Under a Normovolemic Fluid Protocol.

OBJECTIVE: The optimal fluid management for lung resection surgery remains undefined. Concern related to postoperative pulmonary edema has led to the practice of fluid restriction. This practice risks hypovolemia and tissue hypoperfusion. The authors examined the extravascular lung water accumulation and tissue perfusion biomarkers under protective lung ventilation and normovolemia. DESIGN: A prospective observational study. SETTING: A single-center study. PARTICIPANTS: Forty patients aged 18 years or older undergoing lung resection surgery. INTERVENTION: Patients were maintained on protective lung ventilation and a normovolemic fluid protocol. Hemodynamic variables, including global end-diastolic volume index, cardiac index, and extravascular lung water index, together with tissue perfusion biomarkers, including serum creatinine, lactic acid, central venous oxygen saturation, and brain natriuretic peptide, were measured perioperatively. Parametric or nonparametric techniques were used to assess changes of these parameters over 72 hours postoperatively. MEASUREMENTS AND MAIN RESULTS: The global end-diastolic volume index was maintained; cardiac index was increased, without a significant change in extravascular lung water index. Acute kidney injury based on AKIN criteria occurred in 3 patients (7.5%), and in 1 patient (2.5 %) based on RIFLE criteria. Lactic acid and central venous oxygen saturation remained within normal limits, and brain natriuretic peptide showed an insignificant increase. CONCLUSION: In patients undergoing lesser lung resections, a fluid protocol targeting normovolemia together with protective lung ventilation did not increase extravascular lung water. These results suggest further study to identify the optimal fluid regimen to mitigate pulmonic and extrapulmonic complications after lung resection.

Fluid management in thoracic surgery.

PURPOSE OF REVIEW: This review presents the current available data to date regarding the perioperative risks associated with fluid management in thoracic surgery and its implications on the development of acute lung injury (ALI) as well as acute kidney injury (AKI). RECENT FINDINGS: The debate over the adequate fluid management during lung resection surgery has not been settled. Recent findings question the relationship between fluid administration and the development of ALI after lung resection surgery. New concepts including the capillary glycocalyx and the 'baby lung' model have reshaped thinking and therapy. Currently, there has been a growing interest in tissue hypoperfusion resulting from inadequate fluid resuscitation and the development of AKI after lung resection surgery. SUMMARY: Alternative fluid regimens to the traditional restrictive protocols used during thoracic surgery are being explored. These include normovolemic and goal-directed therapy protocols and the use of newer colloid solutions.

Tubular carcinoma of the breast: a retrospective analysis and review of the literature.

BACKGROUND: The favorable prognosis associated with tubular carcinoma of the breast has led some studies to propose less aggressive treatments for patients with this disease. This study aims to address the extent of therapy needed for tubular patients. METHODS: A retrospective review identified 73 cases of tubular carcinoma treated at the Massachusetts General Hospital between 1980 and 2002. Primary treatment was conservative surgery (CS) plus radiation therapy (RT) in 67%, CS without RT in 18%, and mastectomy in 15%. Median follow-up time was 90.5 months. The published literature of 529 conservatively treated tubular carcinomas was reviewed along with the 62 conservative cases from this series. : No patients developed distant metastasis or died from this disease. Local failure occurred in three (4%) of the cases, after 13, 84 and 121 months. All three had initially been treated with CS + RT. Five cases were node-positive, three of which were associated with a primary tumor smaller than 1 cm. Thirteen women, with a median age of 74, were treated by CS without RT and none recurred. A literature review showed that adjuvant RT reduces local failure following CS for tubular carcinoma. CONCLUSIONS: Tubular carcinoma is associated with an excellent prognosis, but long-term follow-up is essential for detecting local failures and a small primary tumor size does not preclude nodal involvement. Adjuvant RT reduces the incidence of local failure following CS for tubular carcinoma, however, elderly women treated by CS may have a very low risk of local recurrence without adjuvant RT.

Is a reduction in radiation lung volume and dose necessary with paclitaxel chemotherapy for node-positive breast cancer?

PURPOSE: To evaluate and quantify the effect of irradiated lung volume, radiation dose, and paclitaxel chemotherapy on the development of radiation pneumonitis (RP) in breast cancer patients with positive lymph nodes. METHODS AND MATERIALS: We previously reported the incidence of RP among 41 patients with breast cancer treated with radiotherapy (RT) and adjuvant paclitaxel-containing chemotherapy. We recorded the central lung distance, a measure of the extent of lung included in the RT volume, in these patients. We used this measure and the historical and observed rates of RP in our series to model the lung tolerance to RT in patients receiving chemotherapy (CHT) both with and without paclitaxel. To evaluate the risk factors for the development of RP, we performed a case-control study comparing paclitaxel-treated patients who developed RP with those who did not, and a second case-control study comparing patients receiving paclitaxel in addition to standard CHT/RT (n = 41) and controls receiving standard CHT/RT alone (n = 192). RESULTS: The actuarial rate of RP in the paclitaxel-treated group was 15.4% compared with 0.9% among breast cancer patients treated with RT and non-paclitaxel-containing CHT. Our mathematical model found that the effective lung tolerance for patients treated with paclitaxel was reduced by approximately 24%. No statistically significant difference was found with regard to the dose delivered to specific radiation fields, dose per fraction, central lung distance, or percentage of lung irradiated in the case-control study of paclitaxel-treated patients who developed RP compared with those who did not. In the comparison of 41 patients receiving RT and CHT with paclitaxel and 192 matched controls receiving RT and CHT without paclitaxel, the only significant differences identified were the more frequent use of a supraclavicular radiation field and a decrease in the RT lung dose among the paclitaxel-treated patients. This finding indicates that the major factor associated with development of RP was paclitaxel treatment. CONCLUSIONS: The use of paclitaxel chemotherapy and RT in the primary treatment of node-positive breast cancer is likely to increase the incidence of RP. In patients treated with paclitaxel, reducing the percentage of lung irradiated by 24% should reduce the risk of RP to 1%, according to our calculations of lung tolerance. Future clinical trials using combination CHT that includes paclitaxel and RT should carefully evaluate the incidence and severity of RP and should also accurately monitor the extent of lung included within the RT volume to develop safe guidelines for the delivery of what is becoming standard therapy for node-positive breast cancer.

Paclitaxel decreases the interstitial fluid pressure and improves oxygenation in breast cancers in patients treated with neoadjuvant chemotherapy: clinical implications.

PURPOSE: It has been hypothesized that tumors with high interstitial fluid pressure (IFP) and/or hypoxia respond poorly to chemotherapy (CT) because of poor drug delivery. Preclinical studies have shown that paclitaxel reduces the IFP and improves the oxygenation (pO(2)) of tumors. Our aim is to evaluate the IFP and pO(2) before and after neoadjuvant CT using sequential paclitaxel and doxorubicin in patients with breast cancer tumors of >/= 3 cm. PATIENTS AND METHODS: Patients were randomly assigned, according to an institutional review board-approved phase II protocol, to receive neoadjuvant sequential CT consisting of either four cycles of dose-dense doxorubicin at 60 mg/m(2) every 2 weeks followed by nine cycles of weekly paclitaxel at 80 mg/m(2) (group 1) or vice versa, with paclitaxel administered before doxorubicin (group 2). Patients were re-evaluated clinically and radiologically. The IFP (wick-in-needle technique) and pO(2) (Eppendorf) were measured in tumors at baseline and after completing the administration of the first and second drug. RESULTS: IFP and pO(2) were measured in 54 patients at baseline and after the first CT. Twenty-nine and 25 patients were randomly assigned to groups 1 and 2, respectively. Paclitaxel, when administered first, decreased the mean IFP by 36% (P = .02) and improved the tumor pO(2) by almost 100% (P = .003). In contrast, doxorubicin did not have a significant effect on either parameter. This difference was independent of the tumor size or response measured by ultrasound. CONCLUSION: Paclitaxel significantly decreased the IFP and increased the pO(2), whereas doxorubicin did not cause any significant changes. Tumor physiology could potentially be used to optimize the sequence of neoadjuvant CT in breast cancer.

Risk of lymphedema after regional nodal irradiation with breast conservation therapy.

PURPOSE: To evaluate the risk factors for lymphedema in patients receiving breast conservation therapy for early-stage breast cancer. METHODS AND MATERIALS: Between 1982 and 1995, 727 Stage I-II breast cancer patients were treated with breast conservation therapy at Massachusetts General Hospital. A retrospective analysis of the development of persistent arm edema was performed. Lymphedema was defined as a >2-cm difference in forearm circumference compared with the untreated side. The median follow-up was 72 months. Breast and regional nodal irradiation (BRNI) was administered in 32% of the cases and breast irradiation alone in 68%. RESULTS: Persistent arm lymphedema was documented in 21 patients. The 10-year actuarial incidence was 4.1%. The median time to edema was 39 months. The only significant risk factor for lymphedema was BRNI. The 10-year risk was 1.8% for breast irradiation alone vs. 8.9% for BRNI (p = 0.001). The extent of axillary dissection did not predict for lymphedema even within the subgroups of patients defined by the extent of irradiation. Most patients underwent Level I or II dissection. In this subgroup, the lymphedema risk at 10 years was 10.7% for BRNI vs. 1.0% for breast irradiation alone (p = 0.0003). CONCLUSION: Nodal irradiation was the only significant risk factor for arm lymphedema in patients receiving breast conservation therapy for early-stage breast cancer. Our data suggest that this risk is low with Level I/II dissection and breast irradiation. However, even after the addition of radiotherapy to the axilla and supraclavicular fossa, the development of lymphedema was only 1 in 10, lower than generally recognized.