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Prashant N Chhajed

Publications and source records attributed to Prashant N Chhajed.

At least 37 records · Page 2Linked to original sources

Treated cytomegalovirus pneumonia is not associated with bronchiolitis obliterans syndrome.

The association of cytomegalovirus (CMV) infection with the development of bronchiolitis obliterans syndrome (BOS) is unclear. We studied 341 lung transplant recipients to assess whether histopathologically diagnosed CMV pneumonia treated with ganciclovir was a risk factor for development of BOS and patient survival. We also analyzed the relationship between CMV donor/recipient serologic status and BOS plus the temporal association between acute rejection and CMV pneumonia. Freedom from BOS for patients with (n = 151) and without (n = 190) CMV pneumonia was 83 and 90% (1 year), 52 and 56% (3 years), and 29 and 38% (5 years), respectively (p = 0.2660). Cumulative survival of patients with and without CMV pneumonia was 90 and 93% (1 year), 70 and 74% (3 years), and 58 and 63% (5 years), respectively (p = 0.1811). There were no significant differences in either development of BOS or patient survival with any combination of donor/recipient serostatus for CMV. Acute rejection occurred in the month preceding CMV pneumonia in 62 of 193 (32%) cases. Histopathologically confirmed CMV pneumonia treated with ganciclovir is not a risk factor for BOS or patient survival, nor is any particular CMV serologic donor/recipient group. CMV pneumonia often follows acute rejection, perhaps as a result of augmented immunosuppression.

Adolescent↗

Sexual health issues after lung transplantation: importance of cervical screening.

To determine the incidence and outcomes of human papillomavirus infection and cervical abnormalities after lung transplantation, we performed a retrospective cross-sectional study of all 166 female recipients who underwent transplantation between February 1989 and June 2001 at our institution. The incidence of low-grade epithelial abnormality of the cervix, cervical intra-epithelial neoplasia (CIN) 1, and the earliest pre-cancerous changes of the cervical epithelial cells, CIN 3, in the post-transplant cohort was 42.2 and 30, respectively, per 1000 women screened compared with 8.3 and 6.2 per 1000 women screened (20-69 years old) in a large reference population. We conclude that the incidence of cervical abnormalities in lung transplant recipients is significantly greater than in the general population. The importance of regular surveillance in immunosuppressed patients to decrease the burden of disease from this potentially fatal but treatable condition is emphasized.

Adult↗

Role of flexible bronchoscopy in lung transplantation.

Flexible bronchoscopy with bronchoalveolar lavage and transbronchial biopsy has contributed significantly to the success of lung transplantation to detect rejection and infections (bacterial, fungal, viral, and protozoal). It permits the visualization of the airway anastomosis and also allows for the management of airway complications using interventional bronchoscopic techniques such as balloon dilatation, stent insertion, and laser. A new classification (TEGLA [thickness, extent of injury, granulation tissue, loose sutures, anastomotic complications]) for uniform reporting of airway ischemic injury is proposed. The common complications during flexible bronchoscopy include acute hypoxemia, bleeding, and pneumothorax. The management of these complications during flexible bronchoscopy and the value of surveillance and follow-up transbronchial biopsy and bronchoalveolar lavage is discussed. Bronchoalveolar lavage and transbronchial biopsy are also used for research purposes and might hopefully allow recognition of bronchiolitis obliterans at an earlier stage.

Journal Article↗

Cutaneous carbon dioxide monitoring in adults.

PURPOSE OF REVIEW: Arterial blood gas analysis is the 'gold standard' method to measure the arterial partial pressure of carbon dioxide (PaCO2). However, arterial sampling including arterial catheterization is invasive and expensive. Cutaneous carbon dioxide tension (PcCO2) measurement is used as a noninvasive surrogate measure of PaCO2, which is used to either estimate PaCO2 or determine trend changes in the measurement. There has been considerable progress in the technical aspects of PcCO2 monitoring in the last few years. In this article, we evaluate recent developments and the renewed interest in the subject of PcCO2 monitoring in adults and discuss the technical aspects, clinical applications and the future outlook for this technique in the clinical setting. RECENT FINDINGS: With evolution in technology, PcCO2 monitoring is now less cumbersome than before. Combined PcCO2 measurement and pulse oximetry is now possible with a single earlobe sensor. SUMMARY: The clinical settings in which PcCO2 monitoring can be applied include patient monitoring during and after anaesthesia, patients receiving noninvasive ventilation, post extubation, endoscopy under sedation, the sleep laboratory and the lung function laboratory. Although there is an overlap of the clinical indications when both PcCO2 and end-tidal carbon dioxide monitoring may be used, it is our opinion that both these methods have independent indications and are sometimes also complementary to each other in patient care.

Journal Article↗

Real-time endobronchial ultrasound-guided transbronchial needle aspiration of mediastinal and hilar lymph nodes.

STUDY OBJECTIVES: Although various techniques are available for obtaining pathology specimens from the mediastinal lymph nodes, including conventional bronchoscopic transbronchial needle aspiration (TBNA), transesophageal ultrasonography-guided needle aspiration, and mediastinoscopy, there are limitations to these techniques, which include low yield, poor access, need for general anesthesia, or complications. To overcome these problems, we undertook the current study to evaluate the clinical utility of the newly developed ultrasound puncture bronchoscope to visualize and perform real-time TBNA of the mediastinal and hilar lymph nodes under direct endobronchial ultrasonography (EBUS) guidance. DESIGN: Prospective patient enrollment. SETTING: University teaching hospital. PATIENTS: From March 2002 to September 2003, 70 patients were included in the study. INTERVENTIONS: The new convex probe (CP) EBUS is integrated with a convex scanning probe on its tip with a separate working channel, thus permitting real-time EBUS-guided TBNA. The indications for CP-EBUS were the diagnosis of mediastinal and/or hilar lymphadenopathy for known or suspected malignancy. Lymph nodes and the surrounding vessels were first visualized with CP-EBUS using the Doppler mode. The dimensions of the lymph nodes were recorded, followed by real-time TBNA under direct EBUS guidance. Final diagnosis was based on cytology, surgical results, and/or clinical follow-up. RESULTS: All lymph nodes that were detected on the chest CT scan could be visualized using CP-EBUS. In 70 patients, CP-EBUS-guided TBNA was performed to obtain samples from mediastinal lymph nodes (58 nodes) and hilar lymph nodes (12 nodes). The sensitivity, specificity, and accuracy of CP-EBUS-guided TBNA in distinguishing benign from malignant lymph nodes were 95.7%, 100%, and 97.1%, respectively. The procedure was uneventful, and there were no complications. CONCLUSIONS: Real-time CP-EBUS-guided TBNA of mediastinal and hilar lymph nodes is a novel approach that is safe and has a good diagnostic yield. This new ultrasound puncture bronchoscope has an excellent potential for assisting in safe and accurate diagnostic interventional bronchoscopy.

Adult↗

Endobronchial ultrasound using a new convex probe: a preliminary study on surgically resected specimens.

The radial endobronchial ultrasound (EBUS) probe is conventionally inserted through the working channel of the flexible bronchoscope and limits interventional diagnostics and therapeutics under direct ultrasound control. The aim of this study was to assess the new convex probe EBUS (CP-EBUS) in the visualization of the hilar lymph nodes in surgically resected specimens and explore its feasibility to perform transbronchial needle aspiration (TBNA) under direct EBUS guidance prior to its clinical use. Fourteen surgically resected specimens from lung cancer (n=12) and metastatic lung cancer (n=2) patients were included in the study. The resected specimens included eight right upper lobes, one right middle lobe, and five left lower lobes. The EBUS examination was performed with a flexible bronchoscope equipped with a 7.5 MHz convex probe (CP) that scans parallel to the insertion direction of the bronchoscope. The appearance of the hilar lymph nodes using this CP-EBUS was noted. The size of hilar lymph nodes was measured at CP-EBUS and compared with the actual size of the lymph nodes, which was measured with a Vernier's caliper. Hilar lymph nodes could be clearly visualized with CP-EBUS. There was a good correlation between the actual size of the lymph node and that measured using CP-EBUS (R(2)=0.950). A dedicated transbronchial aspiration needle could be inserted into the hilar lymph node under direct ultrasonic control. There is a possibility in the underestimation of the size of large lymph nodes due to the scanning nature of the convex probe. The CP-EBUS was successfully used to visualize the hilar lymph node and perform TBNA in surgical resected lung specimens. This technique has an excellent potential to perform direct ultrasound guided TBNA of mediastinal and hilar lymph nodes.

Biopsy, Needle↗

Management of hypoxemia during flexible bronchoscopy.

Under controlled conditions, FB is a safe procedure that has few significant adverse events. Significant hypoxemia may sometimes occur during FB despite the use of supplemental oxygen. UAO has been shown to be the dominant cause of hypoxemia during FB, and this is successfully managed with nasopharyngeal tube insertion. Other strategies that may need to be implemented include oxygen supplementation with intratracheal catheter, administration of sedation reversal medication, removal of the bronchoscope, bag-and-mask ventilation, and, rarely, endotracheal intubation and ventilation. Access to an anesthetist, availability of propofol, backup rigid bronchoscopy, and fluoroscopy are optional but desirable components in the bronchoscopy suite.

Bronchoscopy↗

Risk factors and management of bleeding associated with transbronchial lung biopsy in lung transplant recipients.

The aim of this study was to assess specific risk factors associated with bleeding during transbronchial biopsy (TBBx) in lung transplant recipients. Risk factors analyzed included gender, type of transplant, acute rejection, bronchiolitis obliterans syndrome (BOS) status, infections, number of biopsies obtained per procedures, serum creatinine level and post-operative day since transplantation. The bronchoscope was not wedged to obtain TBBx and associated bleeding was managed using the "back-and-forth" technique. The severity of bleeding is shown to be independent of any specific risk factor and the back-and-forth technique described herein can be safely employed in lung transplant recipients to manage bleeding associated with TBBx performed without wedging of the bronchoscope.

Biopsy↗

Indirect fluorescent antibody testing of nasopharyngeal swabs for influenza diagnosis in lung transplant recipients.

BACKGROUND: Rapid and reliable diagnosis of respiratory viral infections (RVI) in lung transplant recipients is essential to direct therapy of acute graft dysfunction and identify epidemic trends. Traditional techniques of serology and viral culture are limited by the lack of antibody response and delay in diagnosis. METHODS: We examined the clinical utility of indirect fluorescent antibody (IFA) testing in adult lung transplant patients with suspected RVI, compared with serology and culture. Nasopharyngeal and throat swabs (NT) were obtained to sample epithelial cells, followed by application of monoclonal antibody to respiratory syncytial virus, adenovirus, parainfluenza 1-3 and influenza A and B. The Bartels Respiratory Viral Detection kit was used with IFA results available within 24 hours. RESULTS: Nine of 18 patients tested positive for RVI with influenza A (n = 8) and influenza B (n = 1) detected. The sensitivity of IFA (67%) was higher than that of cell culture (45%). With intensive supportive therapy, infection was self-limiting in bronchiolitis obliterans syndrome (BOS) Grade 0-2 patients. However, patients with BOS Grade 3 manifested an acute exacerbation of airflow obstruction, which proved to be irreversible. CONCLUSIONS: Lung transplant patients with "flu-like" symptoms should proceed to IFA testing of NT swab specimens for early diagnosis. Samples collected within 7 days of symptom onset have high sensitivity as compared with serology and viral culture techniques.

Adolescent↗

Ultraflex stents for the management of airway complications in lung transplant recipients.

OBJECTIVE: We present our experience with the use of the Ultraflex (nitinol) stents in the management of airway complications in lung transplant (LT) recipients. METHODOLOGY: Nine LT recipients underwent insertion of uncovered Ultraflex stents. Mean change in FEV1, duration to formation of granulation tissue and follow-up post-stent insertion were compared with results obtained in LT recipients who had undergone Gianturco stent (n = 10) and Wallstent insertion (n = 16). RESULTS: Mean improvement in FEV1 after insertion of Gianturco, Wallstent and Ultraflex stents was 670 +/- 591 mL, 613 +/- 221 mL and 522 +/- 391 mL, respectively. No patient with an Ultraflex stent developed mucus plugging or stenosis at stent extremity at a follow up of 263 +/- 278 days. The mean and median duration to stenosis at stent extremity for patients with Gianturco stents was 102 +/- 85 days and 73 days, respectively, compared with 132 +/- 87 days and 142 days, respectively, for patients with Wallstents. Stricture formation in the middle of the Ultraflex stent occurred bilaterally, at the level of anastomosis in one patient in whom stent placement was undertaken in the presence of inflammation. Stent migration in one patient was related to undersizing of the stent diameter relative to the airway diameter. A larger diameter relative stent was subsequently inserted successfully. CONCLUSION: Ultraflex stents appear to have fewer long-term complications when used in the management of airway complications following LT.

Adult↗

Radiofrequency heat ablation for lung tumors: potential applications.

Radiofrequency ablation (RFA) is an image guided percutaneous procedure using thermal energy that is used to treat malignant lesions in various organs including liver, breast and lungs. It has also been used bronchoscopically to treat endobronchial tumors. Current passing through tissue from the active electrode leads to ion agitation, which is converted by means of friction into heat leading to irreparable cellular damage and coagulation necrosis. The potential benefits include decreased cost and morbidity, treating patients who are not surgical candidates due to age, co-morbidity or extent of disease and the possibility of performing the procedure on an outpatient basis. The aim is usually to reduce tumor size. Whether it can be used with a curative intent in well localized primary tumors remains to be determined by well designed studies. However, caution should be exercised because selective tumor resection is not the gold standard to treat potentially resectable lung malignancies that are treated with lobectomy. Obviously, lung volume reduction surgery combined with tumor resection has challenged this approach. RFA might be the treatment of choice for multiple lung metastases that are usually approached surgically for long-term remission. A specific indication may also be bilateral pulmonary metastases. Other potential applications might be tumor size reduction by a non-surgical procedure followed by adjuvant chemotherapy. Currently, these thoughts remain only speculations, until proven by clinical trials with medium to long-term follow up. Furthermore, the risk of this procedure for pulmonary application has to be better defined.

Catheter Ablation↗

Anti-viral prophylaxis reduces the incidence of lymphoproliferative disease in lung transplant recipients.

BACKGROUND: Post-transplant lymphoproliferative disease (PTLD) is a serious, often fatal complication after solid organ transplantation. Primary Epstein-Barr virus (EBV) infection is the major risk factor for PTLD after lung transplantation, with 30% to 50% of EBV-naive patients who seroconvert and are diagnosed with PTLD. METHOD: In this study, we analyzed the incidence of PTLD in lung and heart-lung transplant recipients before 1996 (historic group) and then compared the impact of long-term anti-viral prophylaxis on the development of PTLD in EBV-seronegative recipients from January 1996 to December 2000 (post-1996 group). Routine induction therapy was not given after 1995. Patients not surviving 30 days, 25 of 341 (7.3%), were excluded. RESULTS: Historic group: PTLD developed in 7 of 167 (4.2%) patients, at a mean of 394 +/- 278 (95-885) days. The mortality was 87.5% at a mean follow-up of 186 +/- 207 (17-520) days after diagnosis. Post-1996 group: Eighteen of 149 (12.3%) patients were EBV seronegative at the time of transplantation, and of these 15 (83%) began receiving continuous anti-viral prophylaxis: acyclovir or valacyclovir or ganciclovir from January 1996. None of the EBV-seronegative recipients receiving continuous anti-viral prophylaxis were diagnosed with PTLD; however, 1 of 3 (33%) of the EBV-seronegative recipients who did not receive anti-viral prophylaxis were diagnosed with PTLD. In the EBV-seronegative recipients, no deaths had been caused by PTLD at a mean follow-up of 806 +/- 534 (39-1,084) days. In the post-1996 group, PTLD developed in 1 of 131 (0.76%) EBV-seropositive recipients. CONCLUSION: Continuous, specific anti-viral prophylaxis in high-risk EBV-seronegative recipients significantly reduces the incidence of PTLD after lung transplantation in the absence of induction therapy.

Acyclovir↗

Mycoplasma hominis infection in heart and lung transplantation.

"Culture-negative" wound infection and mediastinitis secondary to Mycoplasma hominis have been reported after cardiothoracic surgery but no case cluster has ever been described. We report 4 cases of infection in 3 cardiac and 1 bilateral sequential lung transplant recipient over 3 weeks of hospitalization. Successful treatment was achieved with early aggressive surgical intervention and combination antibiotics of clindamycin, doxycycline and/or ciprofloxacin. This cluster raises the question of nosocomial transmission of infection and supports a recommendation for single-room isolation and universal precautions for infected individuals.

Adolescent↗

Prospective analysis of 1,235 transbronchial lung biopsies in lung transplant recipients.

OBJECTIVE: Fiber-optic bronchoscopy with multiple transbronchial lung biopsies (TBB) is the gold standard of evaluation of the pulmonary allograft post-lung transplantation (LT). However, controversy exists regarding the need for surveillance procedures and number of biopsy specimens required for satisfactory yield. The potential morbidity in obtaining multiple TBB specimens remains poorly described. We report the largest series of TBB in LT recipients to date, highlighting the occurrence of acute rejection and infection for surveillance and diagnostic procedures. The safety of TBB is analyzed and a biopsy schedule proposed. METHODS: Prospective analysis of 1,235 TBB in 230 LT recipients performed at St Vincent's Hospital from January 1995 to June 2000. RESULTS: Eight hundred thirty-six (67.7%) TBB were performed as surveillance and 399 (32.3%) for a clinical indication. No significant acute rejection (AR) or infection was disclosed in 53.3% of procedures. The Lung Rejection Study Group requirement of at least five pieces of evaluable lung parenchyma was achieved in 98.2% of procedures. The average number of evaluable fragments per procedure was 6.4, whereas only 3 TBB (0.24%) contained no lung parenchyma and 44 (3.6%) no bronchial wall. Histologic features of AR, lymphocytic bronchiolitis or infection were found in 18.9% of surveillance and 86.4% of clinical TBBs. The yield of surveillance procedures between 4 and 12 months was just 1.1% for cytomegalovirus and 6.1% for AR. The overall complication rate was 6.35% with no deaths recorded. CONCLUSION: Taking 10 to 12 TBB specimens has a high diagnostic yield and rarely fails to provide adequate tissue. The role of surveillance procedures post-lung transplantation remains controversial.

Adolescent↗

Resolution of native lung pneumothorax by insertion of a nitinol stent for bronchostenosis in the transplanted lung.

Following single lung transplantation, the native lung remains a potential source of morbidity from spontaneous pneumothorax, hyperinflation, bacterial and fungal infection and malignancy. The case of a single lung transplant recipient for idiopathic pulmonary fibrosis who developed a recurrent, non-resolving, spontaneous multiloculated pneumothorax in the native lung following thoracoscopic talc pleurodesis is reported. The pneumothorax ultimately resolved following insertion of a nitinol stent for coexisting bronchostenosis in the transplanted lung. In a single lung transplantation recipient in whom a native lung pneumothorax reoccurs or persists despite appropriate initial management, it may be useful to undertake bronchoscopy to exclude the possibility of bronchostenosis in the transplanted lung.

Adult↗

Management of acute hypoxemia during flexible bronchoscopy with insertion of a nasopharyngeal tube in lung transplant recipients.

STUDY OBJECTIVES: To assess the utility of nasopharyngeal tube insertion in the management of hypoxemia during flexible bronchoscopy (FB) in lung transplant recipients, and to determine the incidence and risk factors of upper-airway obstruction (UAO) leading to significant hypoxemia during FB. SETTING: Heart-lung transplant unit of a university hospital. PATIENTS AND METHODS: Ninety-six lung transplant recipients (47 men and 49 women; mean +/- SD age, 41.4 +/- 13.1 years) underwent 714 FB procedures from January 1997 to May 2000. INTERVENTION: A fall in oxygen saturation (< or = 90%) in patients receiving 6 L/min of oxygen via nasal prongs was treated with insertion of a nasopharyngeal tube, continued oxygen supplementation, and withdrawal of the bronchoscope to the trachea. If oxygen desaturation persisted at < 90% despite additional oxygen administration via a 7F catheter placed either just above the larynx or in the proximal trachea, the bronchoscope was withdrawn, reversal of sedation was administered, and bag and mask ventilation was instituted until satisfactory spontaneous ventilation was achieved. RESULTS: Forty-six patients (47.9%) were treated with nasopharyngeal tube insertion on 102 occasions at a mean duration of 168 +/- 178 days after lung transplantation. In 90 of 102 procedures (88.2%), significant hypoxemia due to UAO was successfully treated with nasopharyngeal tube insertion. The mean oxygen saturation after nasopharyngeal tube insertion was 97 +/- 3%. Male gender, increase in body mass index after lung transplantation, and presence of obstructive sleep apnea were significant factors associated with the need for nasopharyngeal tube insertion during FB in lung transplant recipients. CONCLUSIONS: Significant oxygen desaturation during FB in lung transplant recipients is mainly due to UAO. Insertion of a nasopharyngeal tube is a novel and a highly effective approach to the management of acute hypoxemia during FB.

Adult↗