back to blog roll

How important is nutritional assessment in hyperbaric oxygen therapy? 

One of the keys to a successful patient outcome is assessing nutritional status. If the patient is malnourished, there is insufficient nutritional substrate from which to build new tissue to heal a wound.[1] One out of three patients treated at hyperbaric services can be at risk of malnutrition. 

Patients receiving hyperbaric oxygen therapy (HBOT) for non-healing wounds (e.g., diabetic foot ulcers - DFUs) and osteoradionecrosis are most at risk of malnutrition.[2] 

The definition of a nutritional assessment in the National Coverage Determination NCD 20.29 for Hyperbaric Oxygen Therapy [3] is vague. Although an assessment of nutritional status should be routinely performed on all patients seen in the outpatient wound clinic, the protocol is not well defined. Many times the patient’s nutritional evaluation and management is directed back to the primary care or referring physician. 

NCD 20.29 states: "For diabetic wounds of the lower extremity, the use of HBO therapy is covered as adjunctive therapy only after there are no measurable signs of healing for at least 30 days of treatment with standard wound therapy and must be used in addition to standard wound care".[3] Standard wound care in patients with diabetic wounds includes optimization of nutritional status.[4] Since the NCD requires this to be part of conservative care, documentation of nutritional status must be a part of the wound care and HBOT patient record. If this documentation is missing, the services may be denied post payment and funds recouped upon review by your Medicare Administrative Contractor (MAC).

How is optimization of nutritional status defined?

The requirements are not well defined by the NCD or most MACs (i.e., WPS, Novitas). Noridian has proposed that "...a basic assessment of the patient’s metabolic stability and adequacy of nutritional support should be included in the Plan of Care (treatment plan). Some expected parameters indicating this metabolic stability might be recently documented CBC, BUN/Creatinine (serum), albumin/pre-albumin (serum), glucose and hemoglobin A1C (serum). Patients who are not following the expected progression of wound healing should have a formal nutritional assessment, using a standardized assessment such as the ASPEN criteria."[5] (See topic "How to Screen, Assess and Manage Nutrition in Patients with Wounds").

Thus, we suggest that laboratory documentation of nutritional status include the parameters listed above, with vitamin and trace mineral levels as clinically indicated. Also, since inflammation alters the levels of these markers, C-reactive protein may be of use in interpreting results.


Protein deficiencies are thought to contribute to poor healing rates. Proteins play the most important role throughout the entire wound-healing process. Cells of the immune system (e.g. lymphocytes, leukocytes, phagocytes, monocytes, and macrophages) are mainly comprised of proteins and are necessary to initiate a healthy inflammatory response in the healing process. An adequate supply with proteins is necessary for consistent wound healing. Because collagen is the protein that is produced mainly in the healing wound, a lack of protein decreases the synthesis of collagen and the production of fibroblasts.[6] 

According to the NCD 20.29, patients with DFUs require 30 days of optimization of all parameters.[3] Using this timeframe, transferrin and prealbumin levels would show the greatest changes in the time period that is being reviewed (see Table 1 below).

Table 1. Protein laboratory markers and their half-life and normal ranges



14-20 DAYS

3.5 to 5.5 g/dL


8-9 DAYS

Adults: 20%-50%


2-3 DAYS

18-36 mg/dL

The initial intervention should consist of oral nutritional supplements such as high protein/high-calorie food items (e.g. eggs, meats, nuts, cheese, and prepackaged dietary supplements that include arginine, glutamine, and/or hydroxyl-methyl-buterate HMB).

Patients who are unable to adequately increase their protein consumption by simple oral nutritional supplements should be considered for tube feedings or parenteral nutritional support. Evaluation by a registered dietitian should be considered if there is an inadequate response to first-line oral interventions.

The body creates protein waste products when it ingests protein. In healthy kidneys, millions of nephrons filter waste products. If a patient has chronic kidney disease (CKD), the kidney loses the ability to remove protein waste. This waste builds up in the blood instead of being flushed out into the urine. Patients with CKD should consult their nephrologist or a registered dietician before increasing protein intake. 

Patients who live with diabetes and experience delayed wound healing should balance optimization of nutrition with glycemic control. A multidisciplinary approach may be necessary to achieve clinical outcomes. Wound Centers should strive to develop a systematic approach to optimizing nutritional status in patients starting with the initial evaluation and reassessing at 30 day intervals. 

Key takeaways

One of the keys to a successful patient outcome in HBOT is assessment of nutritional status. Malnutrition screening should be part of routine patient assessment in order to ensure patients receive timely nutritional intervention. 

NCD 20.29 requires optimization of nutritional status to be part of conservative care thus documentation of nutritional status, plan and outcomes must be part of the wound care and HBOT patient record.


The WoundReference Hyberbaric Oxygen Therapy Knowledge Base features reimbursement and clinical guidelines, protocols and tools to promote high standards of patient care and operational safety within the hyperbaric program, including comprehensive topics related to Patient Care in HBOT.  WoundReference Curbside Consult gives you actionable, specific answers from our multidisciplinary advisory panel in a timely manner. More topics and tools on nutrition in wound care HBOT will be released soon. 


  1. Wild Thomas, Rahbarnia A, Kellner M, Sobotka L, et al. Basics in nutrition and wound healing; Nutrition 26 . 2016;.
  2. See HG, Tan YR, Au-Yeung KL, Bennett MH et al. Assessment of hyperbaric patients at risk of malnutrition using the Malnutrition Screening Tool - a pilot study. Diving and hyperbaric medicine. 2018;volume 48(4):229-234.
  3. CMS. National Coverage Determination (NCD) for Hyperbaric Oxygen Therapy (20.29) . 2017;.
  4. Gelly H, et al. Today’s Wound Clinic . 2016;.
  5. Noridian. Proposed Local Coverage Determination for Wound Care (DL38904)
  6. Collins N, Friedrich L, et al. Appropriately Diagnosing Malnutrition to improve wound healing; Today’s Wound Clinic . 2016;.

About the Authors

With over four decades of healthcare experience, Jeff currently holds the position of Principal Partner at Midwest Hyperbaric LLC and the Co-founder and Chief Clinical Officer of Wound Reference. Jeff has excelled in critical care throughout his career, devoting almost a decade as a Flight Respiratory Therapist/Paramedic for the Spirit of Kansas City Life Flight. In 1993, Jeff transitioned into the field of Hyperbaric Medicine and Wound Care, where he committed 21 years of his career to serving as the Program Director for a 24/7 Level 1 UHMS Accredited facility with Distinction. In this role, he continued to provide patient care while overseeing all administrative, clinical, and daily operations within the Wound Care and Hyperbaric Facility. Jeff is a Registered Respiratory Therapist and a Certified Hyperbaric Technologist (CHT). He has also undergone training as a UHMS Safety Director and a UHMS Facility Accreditation Surveyor. Jeff currently serves as a member of the UHMS Accreditation Council, the UHMS Accreditation Forum Expert Panel, and the UHMS Safety Committee. Additionally, he is an esteemed member of the NFPA 99 Hyperbaric and Hypobaric Facilities Technical Standards Committee. Jeff's dedication to the field has earned him numerous prestigious awards. In 2010, he received the Gurnee Award, which honored his outstanding contributions to undersea and hyperbaric medicine. Three years later, in 2013, he was awarded the Paul C. Baker Award for his commitment to Hyperbaric Oxygen Safety Excellence. Most recently, in 2020, Jeff was honored with "The Associates Distinguished Service Award (UHMSADS)," a recognition reserved for exceptional Associate members of the Society who have demonstrated exceptional professionalism and contributions deserving of the highest accolades.
An Advanced Certified Hyperbaric Registered Nurse and Certified Wound Specialist with expertise in billing, coding and reimbursement specific to hyperbaric medicine and wound care services. UHMS Accreditation Surveyor and Safety Director. Principal partner of Midwest Hyperbaric LLC, a hyperbaric and wound consultative service. Tiffany received her primary and advanced hyperbaric training through National Baromedical Services in Columbia South Carolina. In 2021, Tiffany received the UHMS Associate Distinguished Service Award. "This award is presented to individual Associate member of the Society whose professional activities and standing are deemed to be exceptional and deserving of the highest recognition we can bestow upon them . . . who have demonstrated devotion and significant time and effort to the administrative, clinical, mechanical, physiological, safety, technical practice, and/or advancement of the hyperbaric community while achieving the highest level of expertise in their respective field. . . demonstrating the professionalism and ethical standards embodied in this recognition and in the UHMS mission.”
Explore our Wound Care and Hyperbaric Solutions