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Waldron, Nathan H.

https://orcid.org/0000-0002-1430-8204

Mayo Clinic

Mayo Clinic in Florida

Citations 3

Feasibility and early experience with venous Doppler congestion assessment in post-operative lung transplant patients
Pandompatam, Govind , Narula, Tathagat , Alvarez, F G, Balasubramanian, Prasanth, Milian, Ricardo Diaz , Waldron, Nathan, Kalagara, Hari, Diaz Milian, Ricardo , Alvarez, Francisco , Balasubramanian, Prasanth , Waldron, Nathan H. , Kalagara, Hari

The Ultrasound Journal | May 21, 2026 | Volume: 18 | Issue: 1 | Pages: 18681

10.5826/tuj.2026.18681 Get It

Background: The role of venous Doppler ultrasound in assessing venous congestion in the setting of post-lung transplantation surgery is unknown. We performed a feasibility study on the use of venous Doppler ultrasound in the immediate post-operative period after lung transplantation in a retrospective, single-center observational evaluation. Patients had at least two venous congestion Doppler ultrasound exams involving interrogation of IVC diameter, hepatic vein, portal vein and renal vein Doppler assessments. Results: A total of 9 patients were included in our study with a median age of 60 years, 66.7% being male, and a median BMI of 20.9. All patients had VExUS grade ≥1 on their first venous Doppler exam. All nine patients had a decrease in portal vein pulsatility from initial to final exams. Correlation between portal venous pulsatility and net fluid balance was not statistically significant R= 0.33 (P= 0.39). Other parameters, including VExUS grade, IVC diameter, HV and RV Doppler changes from initial to final ultrasound exams showed variable changes in the post-operative period. Conclusion: Venous congestion Doppler ultrasound assessments appear feasible in immediate postoperative lung transplant patients. A multitude of factors beyond fluid status likely affect waveforms.
Assessing Right Ventricle Over Time in Patients on Veno-Venous Extracorporeal Membrane Oxygenation: Insights From Serial Echocardiography
Isha, Shahin , Narra, Sai Abhishek, Batool, Humera, Jonna, Sadhana , Giri, Abhishek , Herrmann, Olivia , Dyson, Amari, Nichols, Mick D., Hannon, Rachel, Baz, M., Sanghavi, Devang , Kiley, Sean , Waldron, Nathan H. , Pandompatam, Govind , Rosenbaum, Drew N., Baz, Maher, Waldron, Nathan, Bohman, J Kyle K, Shahin, Isha , Batool, Humera, Herrmann, Olivia, Pham, Si M. , Franco, Pablo Moreno , Baz, Maher, Bohman, J. Kyle , Chaudhary, Sanjay, Guru, Pramod , Bhattacharyya, Anirban

ASAIO Journal | May 31, 2024 | Volume: 70 | Issue: 12 | Pages: 1033-1039

10.1097/mat.0000000000002235 Get It

Extracorporeal membrane oxygenation (ECMO) is often used in acute respiratory distress syndrome (ARDS) with refractory hypoxemia. There is limited literature highlighting the development of right ventricular (RV) failure while on ECMO. We conducted a retrospective multicenter observational study including 70 patients who were placed on veno-venous (VV)-ECMO for respiratory failure at Mayo Clinic, Jacksonville, and Mayo Clinic, Rochester, between January 2018 and June 2022 and had at least two post-ECMO transthoracic echoes. The primary outcomes were the incidence and progression of RV dysfunction and dilatation. The secondary outcome was in-patient mortality. Among 70 patients in our cohort, 60.6% had a normal RV function at the time of ECMO placement, whereas only 42% had a normal RV function at the second post-ECMO echo. On multinomial regression, a moderate decrease in RV function was associated with ECMO flow (odds ratio [OR] = 2.32, p = 0.001) and ECMO duration (OR = 1.01, p = 0.01). A moderately dilated RV size was also associated with ECMO flow (OR = 2.62, p < 0.001) and ECMO duration (OR = 1.02, p = 0.02). An increasing degree of RV dysfunction was associated with worse outcomes. Our study showed that the increasing duration and flow of VV-ECMO correlated with progressive RV dilatation and dysfunction, which were associated with poor survival.
Adding an extension piece to the end of the purge side arm of the Impella device can prevent the incidence of the cassette breaking and decrease the Impella device failure rate: Impact of practice change on patient outcome
SATASHIA, PARTHKUMAR , White, Andrew D. , Isha, Shahin , Hanson, Abby , Jenkins, Anna , Blasavage, Jessica, Matos, Nikki , Tomlinson, Amanda, Zhang, Stephanie , Quiñones, Quintin J., Waldron, Nathan H. , Kiley, Sean , Chaudhury, Sanjay, Shapiro, Anna B, Sanghavi, Devang , White, Andrew , Quinones, Quintin, Waldron, Nathan, Guru, Pramod K , Sanghavi, Devang K., Jenkins, Anna S , Shahin, Isha , White, Andrew, Bhattacharyya, Anirban , Guru, Pramod , Franco, Pablo Moreno

Perfusion | December 7, 2023 | Volume: 39 | Issue: 8 | Pages: 1757-1760

10.1177/02676591231220305 Get It

Background: Impella 5.5® with Smart Assist is a minimally invasive Left Ventricular Assist Devices (LVAD) approved by the Food and Drug Administration (FDA) for treating ongoing cardiogenic shock for up to 14 days. The Impella® intends to reduce ventricular workload and provide the circulatory support necessary for myocardial recovery. Research Question: Compared to standard practice, does adding an extension piece to the purge tube side arm of the Impella® Device decrease the incidence of device failure and positively impact the health outcome of adult patients receiving Impella® support? Study Design and Methods: A retrospective chart review of ICU patients was done at a tertiary care center from August 2018 to August 2022 to assess the differences in patient outcomes related to Impella® Device utilization before and after the implementation of the extension piece to the purge tube sidearm. Among patients reviewed, a total of 20 were included in our review, with seven not having the purge tube side arm extension added, while 13 patients had the extension. Results: The two study groups had no significant difference in patient health outcomes. Additionally, there were no instances of device failure requiring explanation without the extension tubing. However, there were no cases of the purge cassette cracking with the addition of the extension tubing. Conclusion: The addition of extension tubing to the purge cassette of the Impella® Device did not impact patient health outcomes or the incidence of device failure. There was a complete reduction in the incidence of the purge cassette cracking, which could reduce the potential for infection or device failure over a long period of mechanical support. There is a need for long-term prospective studies to confirm the results.