Leadership Team

Enhance is led by experienced physicians and healthcare executives who have an unparalleled track record of measurably improving hospital based physician performance and reducing costs at leading hospitals and health systems nationwide.
Howard Greenfield:

Dr. Howard Greenfield:
Co-Founder and Principal of Enhance Healthcare Consulting, is a board-certified anesthesiologist who has a thorough understanding of the financial and clinical needs of both hospitals and anesthesia providers.
Throughout his career, he has worked with hospitals and providers to align incentives and develop cost effective and timely solutions to OR management. In addition, he has expertise in optimizing anesthesia group and OR performance by working collaboratively with hospital administration, surgeons, operating room nurses and anesthesiologists nationwide.
He was one of the original founding partners of Sheridan Healthcare and spent his clinical career at Memorial Regional Hospital in Hollywood, Florida. As Chief of the Anesthesia Department, he provided clinical and operational oversight to an Anesthesia care team working in 24 operating rooms.
In 2005, he became Clinical Administrator of Anesthesia Operations at Sheridan Healthcare and later promoted to Vice President of Business Development & Recruiting where he led the organic growth of the Anesthesia division as well as hospital based physician group acquisition across a variety of specialties.
Dr. Greenfield is a graduate of Tulane University and of Temple University School of Medicine and completed his anesthesia training at Jackson Memorial/University of Miami.

Robert Stiefal:

Dr. Robert Stiefel, Co-Founder and Principal of Enhance Healthcare Consulting, is a board-certified anesthesiologist who has worked with many of the nation’s largest health systems to deliver sustainable improvement in their ORs and develop strategies to meet the challenges of an ever-changing healthcare environment.

A co-founder of L&S Medical Management, Dr Stiefel helped grow that organization to 140 Clinical providers over 8 years. L&S also featured a large anesthesia billing organization with 60 personnel. L&S was sold in 2002 to Team Health, who DR Stiefel worked with until 2006 as Senior VP of Anesthesia Business Development.

Since 2006 he has been involved in consulting across the country for hospitals and Health Systems, advising on issues related to anesthesia and operating room performance improvement. As a co-founder of Enhance Healthcare he has been a lead consultant on numerous engagements with extensive experience in medical group financial performance and operational improvement.

Dr Stiefel is a graduate of the University of Massachusetts and Tufts University School of Medicine. He completed his anesthesia training as Chief Resident at University of Massachusetts Medical Center and since has had 20 years of experience as a clinician, consultant, and strategist, Dr. Stiefel has led numerous initiatives including re-design of medical group governance, subsidy negotiations, policy/procedures, compensation methodology and implementation.

Robert Johnson:

In May of 2014, Enhance Healthcare added as a Principal, Mr. Robert Johnson MBA. Mr. Johnson is an accomplished healthcare executive with broad experience in multiple healthcare environments.

In his thirteen years at John Hopkins Hospital, Bob started as a technician in the cardiac operating rooms then worked his way up in management and eventually became the Administrator of the Department of Anesthesiology and Critical Care Medicine.

In 1991, Bob left Hopkins and entered the for-profit world to start one of the first national anesthesia practice companies, Anesthesia Partners Inc. After considerable success establishing anesthesia practices in several states for Anesthesia Partners, he returned to academic healthcare management at Duke Hospital as the Senior Associate Chief Operating Officer.
Bob left Duke in 1996 to pursue greater responsibilities in academic medicine and for another ten years served in senior management roles at the Baylor College of Medicine and the University of Pittsburgh.

Mr. Johnson returned to the for-profit world in 2002 as Sheridan Healthcare’s Chief Development Officer. Bob’s efforts helped Sheridan grow in the number of anesthesia practices and the number of states that Sheridan operated practices.

In 2007, Mr. Johnson returned to hospital management as the Vice President of Hospital-Based Physician Services for the Hospital Corporation of America, Inc. (“HCA”). Bob played a critical role for HCA evaluating, operating and leading the negotiations with anesthesia, emergency, radiology and pediatric physician programs.

Steve Gevas:
Is a board-certified and Fellow of the American College of Emergency Medicine.
He held a positon as the Assistant Chairman of the Emergency Department at Shady Grove Adventist Hospital in Gaithersburg. In 1998 he accepted a position as the Chairman of the Department of Emergency Medicine at Parkway Regional Medical Center in North Miami Beach with Sheridan Healthcare.

The Following year, he became the Chief Medical Officer for Emergency Medicine at Sheridan Healthcare and in 2000 was promoted to the position of VP of Emergency Services until July of 2012. Dr. Gevas had operational oversight of all adult and pediatric EM Programs and created an environment that supported excellent teamwork to achieve great results. He worked clinically at all of the Sheridan EM contracts and helped to develop policies and procedures to enhance patient safety, customer satisfaction and throughputs. Dr. Gevas has also been an emergency medicine consultant and the Chief Medical Officer for Proven Results Healthcare since 2013.

Dr. Gevas is an undergraduate of West Virginia University and received his medical doctrine from the University of Maryland. He received his board certification from the American Board of Emergency Medicine in 1987.

Holli Greenfield:

Holli Greenfield oversees Enhance Healthcare Consulting’s operational management including staff education and compliance with Joint Commission standards, contract negotiations, payroll and human resources for over 50 employees.

Ms. Greenfield graduated from Hahnemann/Drexel University School of Nursing in 1991. She began her nursing career at Thomas Jefferson Hospital, and in 1994 relocated to Memorial Regional Hospital in Hollywood, Florida. During her tenure at MRH, Ms. Greenfield was Charge Nurse of a 24 room operating suite and Team Leader for Trauma and Vascular Surgery. In 2002, she became Nurse Manager at Memorial Same Day Surgery Center and was promoted to Administrator in 2008 and remained in that capacity until December 2013.

Lawrence Lottenberg:

Dr. Lottenberg, a consultant at Enhance Healthcare Consulting, is an acute care surgeon recently completing a career at an academic Level I Trauma Center in Gainesville, Florida. He has been a surgeon since 1980 and specializes in trauma, emergency general surgery, elective general surgery, burns and surgical critical care.

He has been the trauma medical director at two different institutions, one at Memorial Regional Hospital in Hollywood, Florida where he developed the Level II trauma center in 1992 and then matriculated that institution to a Level I trauma center in 1999. Most recently he began, organized and staffed the Level I trauma center at the University of Florida in Gainesville.

Dr. Lottenberg has served as the past chairman of the Florida Committee on Trauma and the past president of the Florida Chapter of the American College of Surgeons. He has received numerous teaching awards and has been recognized as an outstanding surgeon by several societies. From 2004 to 2014, he has been an Associate Professor of Surgery and Anesthesiology at the University of Florida College of Medicine. In 2011, he served as the Senior Visiting
Attending Trauma Surgeon for the U.S. Army at Landstuhl Regional Medical Center in Landstuhl, Germany.

Dr. Lottenberg has been responsible for authoring several State of Florida trauma protocols and guidelines over the last 30 years. He is an expert in trauma system inception and analysis and has guided numerous trauma centers with their inception, development and staffing.