Prolonged air leak following upper lobectomy: in search of the key

Air leaks: Stapling affects porcine lungs biomechanics

During thoracic operations, surgical staplers resect cancerous tumors and seal the spared lung. However, post-operative air leaks are undesirable clinical consequences: staple legs wound lung tissue. Subsequent to this trauma, air leaks from lung tissue into the pleural space. This affects the lung's physiology and patients' recovery. The objective is to biomechanically and visually characterize porcine lung tissue with and without staples in order to gain knowledge on air leakage following pulmonary resection. Therefore, a syringe pump filled with air inflates and deflates eleven porcine lungs cyclically without exceeding 10 cmH₂O of pressure. Cameras capture stereo-images of the deformed lung surface at regular intervals while a microcontroller simultaneously records the alveolar pressure and the volume of air pumped. The raw images are then used to compute tri-dimensional displacements and strains with the Digital Image Correlation method (DIC). Air bubbles originated at staple holes of inner row from exposed porcine lung tissue due to torn pleural on costal surface. Compared during inflation, left upper or lower lobe resections have similar compliance (slope of the pressure vs volume curve), which are 9% lower than healthy lung compliance. However, lower lobes statistically burst at lower pressures than upper lobes (p-value<0.046) in ex vivo conditions confirming previous clinical in vivo studies. In parallel, the lung deformed mostly in the vicinity of staple holes and presented maximum shear strain near the observed leak location. To conclude, a novel technique DIC provided concrete evidence of the post-operative air leaks biomechanics. Further studies could investigate causal relationships between the mechanical parameters and the development of an air leak.

A randomized trial of who is better at treating the incomplete pulmonary fissure between stapler and thulium laser

BACKGROUND

The role of thulium laser in the treatment of interlobar fissures in lobectomy is not clear. We aim to evaluate the safety, effectiveness and economy of thulium laser in the treatment of incomplete interlobar fissure during lobectomy.

METHODS

A total of 76 patients were randomly divided into two groups: laser group and stapler group. The laser group was treated with thulium laser and the stapler group was treated with stapler.

RESULTS

Compared with stapler group, the laser group had a longer operation time, more postoperative drainage and lower operation cost while there was no significant difference in hospitalization time, postoperative air leakage time and chest tube duration.

CONCLUSIONS

Thulium laser is safe and effective in the treatment of incomplete interlobar fissure during lobectomy and can reduce the cost.

Pediatric Cryptococcal Lymphadenitis in the Absence of AIDS: Case Report and Literature Review

We present a rare case of cryptococcal lymphadenitis without immunocompromization in a two-and-a-half-year-old child. He was referred to our center with a fifteen-day history of continued fever. Ultrasound and computed tomography (CT) revealed the enlargement of multiple lymph nodes and lung reticulonodular shadows. Hematological, immunological, and microbiological tests for hepatitis, lymphoma, AIDS, and immunoglobulin deficiencies were negative. Laboratory tests demonstrated elevated erythrocyte sedimentation rate, elevated plasma and urinary ß2-microglobulin (ß2-MG) levels, and elevated C-reactive protein and fibrinogen. Both blood routine and bone marrow aspiration showed elevated eosinophil granulocytes. The diagnosis of cryptococcal lymphadenitis was obtained by excisional biopsy of the cervical lymph nodes. The patient was treated with intravenous amphotericin B and oral flucytosine for five weeks, then with subsequent oral fluconazole for three months. The patient is now doing well. Our case suggests that the diagnosis of cryptococcal lymphadenitis is very difficult without etiology and pathology, especially for a patient with a normal immune system; lymph node biopsy is necessary to diagnose it, and immediate antifungal treatment is necessary to treat it.

Results of a prospective algorithm to remove chest tubes after pulmonary resection with high output

OBJECTIVE

Many patients have their hospital discharge delayed because their chest tube drainage is too high, despite the fact that there are no data to support the commonly used 250 mL/day threshold.

METHODS

A retrospective cohort study was conducted with a prospective database and prospective algorithm from one surgeon. All patients underwent elective pulmonary resection. The last chest tube was removed if there was no air leak and nonchylous drainage of 450 mL/day or less.

RESULTS

The study comprised 8608 operations and 2077 patients who underwent an elective (nonpneumonectomy) pulmonary resection via thoracotomy by one general thoracic surgeon over a 10-year period. Eighty-nine patients went home with a chest tube owing to air leak. The remaining 1988 patients were discharged without a chest tube. Types of pulmonary resection were wedge resection in 729 patients, segmentectomy in 214, lobectomy in 1104, and bilobectomy in 30. The median day of discharge was postoperative day 4. One hundred one (5%) were readmitted to the hospital within 60 days of discharge. The most common reason for readmission was dehydration and fatigue. Only 11 (0.55%) had readmissions owing to recurrent symptomatic effusion and most were treated with video-assisted thoracoscopy. Follow-up was 100% at 4 weeks and 93% at 8 weeks.

CONCLUSIONS

Chest tubes can be removed with up to 450 mL/day of nonchylous drainage after pulmonary resection, and perhaps a higher volume could be accepted. Readmission owing to a recurrent effusion is exceedingly uncommon, and the practice of leaving the tube in longer for drainage less than 450 mL/day is unsupported in the literature.

[Persistent air leak (PAL): conservative vs. invasive approach?]

INTRODUCTION

An air leak following pulmonary resection is generally defined as persistent, or prolonged, if it fails to resolve within the first post-operative week. The precise definition has varied from study to study.

STATE OF ART

Persistent air leak represents the most frequent complication in patients undergoing general thoracic procedures. The groups most at risk are elderly patients, patients with chronic obstructive pulmonary disease (COPD), and those who have general risk factors such as diabetes mellitus or who are taking oral steroids. The surgical procedures most commonly affected are upper lobectomies and lung volume reduction surgery for end-stage emphysema.

PERSPECTIVES

Technically, performing a pleural tent at the time of an upper lobectomy may decrease the incidence of prolonged air leak. Reinforcement or buttressing of the staple line has been shown to decrease both the incidence and the duration of air leaks, but this increases costs and should thus be reserved for patients with lung parenchyma at the highest risk. The use of biological glues can be helpful in reducing the duration of chest tube drainage when applied intraoperatively for moderate and/or severe parenchymal air leaks, however, their systematic use in not recommended. The management of chest tube drainage after pulmonary resection varies widely from one institution to another. Most recent reports have favoured early discontinuation of negative pressure drainage and a move to underwater seal drainage (from the second post-operative day), however, no large scale randomised study is yet available to compare this with a more conservative approach.

CONCLUSIONS

The management of persistent air leak following surgery requires identification of risk factors, good surgical technique and appropriate chest tube management.

Characterization and Importance of Air Leak After Lobectomy

BACKGROUND

Air leak after pulmonary resection is a common occurrence that is incompletely characterized. Our objectives were to determine prevalence of air leak and identify its risk factors, characterize its duration and discover its correlates, and evaluate its clinical importance.

METHODS

Air leak was studied in 319 patients undergoing isolated anatomic lobectomy between January 1998 and July 2001. Risk factors for air leak were identified by logistic regression of patient characteristics, indications for lobectomy, lobe resected, and fissure management. Factors associated with air leak duration were sought by time-related analysis. Association of complications with air leak was evaluated by propensity-matched pairs analysis.

RESULTS

Prevalence: Air leak prevalence was 58% (186 patients). It occurred less frequently after left lower lobectomy (p < 0.0001) and later in the series (p = 0.008). It was surgeon dependent (p = 0.007) but not associated with forced expiratory volume in 1 second.

DURATION

The 10th, 50th, and 90th percentiles of air leak duration were 1.6, 3, and 7 days, respectively. No factors, including fissure management, were reliably associated with air leak duration.

IMPORTANCE

Air leak was associated with more complications (30% vs 18%, p = 0.07) and protracted hospital course (p = 0.02).

CONCLUSIONS

Postoperative air leak is a common occurrence after lobectomy, but fortunately it is self-limiting in most patients. Air leak is independently associated with longer hospital stay and other postoperative complications. Surgical technique is important and may be the only modifiable factor.

Predictors of prolonged air leak after pulmonary lobectomy

BACKGROUND

The objective of this study was to identify the predictors of prolonged air leak (air leak longer than 7 days) in patients submitted to pulmonary lobectomy for lung cancer.

METHODS

A retrospective analysis on 588 patients operated on of pulmonary lobectomy from January 1995 through June 2003 was performed. Univariate and logistic regression analyses were performed to generate a model predicting the risk of prolonged air leak. Bootstrap resampling technique was used to validate the regression model.

RESULTS

A prolonged leak was exhibited by 15.6% of patients. Logistic regression analysis demonstrated that significant independent predictors of prolonged air leak were a reduced predicted postoperative forced expiratory volume in 1 second (p < 0.0001), the presence of pleural adhesions (p = 0.003), and upper resections (p = 0.006). Bootstrap resampling analysis confirmed the reliability of these variables. A regression equation was generated for the prediction of the risk of prolonged air leak.

CONCLUSIONS

We report that a low predicted postoperative forced expiratory volume in 1 second, the presence of pleural adhesions, and the upper lobectomy or bilobectomy increased the risk of air leak persisting for more than 7 days. A model was generated to calculate this risk and assist the surgeon in taking extra measures to prevent such complication (ie, optimizing bronchodilator treatment, pleural tent, sealants, buttressed staple lines, water seal, and chest tube drainage).

Predictors of alveolar air leaks

Persistent air leaks are caused by the failure of the postoperative lung to achieve a configuration that is physiologically amenable to healing. The raw pulmonary surface caused by the dissection of the fissure often is separated from the pleura, and the air leak fails to close. Additionally, higher air flow thorough an alveolar-pleural fistula seems to keep the fistula open. Other factors that interfere with wound healing, such as steroid use, diabetes, or malnutrition, can result in persistence of the leak. A thoracic surgeon can minimize the incidence of air leak through meticulous surgical technique and can identify patients in whom the balance of risks (Table 1) and benefits warrant operative intervention based on an understanding of the underlying pathophysiology.