Influences of hyperbaric oxygen on blood pressure, heart rate and blood glucose

Influences of hyperbaric oxygen on blood pressure, heart rate and blood glucose levels in patients with diabetes mellitus - Al-Waili et al. (2006)

Key Points

Hyperbaric oxygen treatment significantly lowers blood glucose in diabetic patients
Hyperbaric oxygen treatment increases blood pressure, especially in those with diabetes or hypertension

The Breathing Diabetic Summary

I am a fan of finding practical results in the scientific literature that we can apply to our lives today. It’s probably not practical to use hyperbaric oxygen every day. Luckily, previous studies have found that slow breathing elicits many of the same responses as hyperoxia, albeit through different mechanisms. So, papers like this intrigue me because we can potentially get similar results by simply breathing lightly and slowly.

Hyperbaric oxygen treatment (HBO2) involves breathing 100% oxygen in a chamber with increased pressure. Previous studies have shown that HBO2 can increase parasympathetic activity, while also increasing catecholamines and inducing vasoconstriction. This is somewhat counterintuitive because vasoconstriction and catecholamines (stress hormones) are associated with the sympathetic nervous system, so I would not expect an increase in parasympathetic activity. However, because we are putting our bodies into an environment that could not be experienced in nature (increased pressure and 100% oxygen), it does not surprise me that we get some unexpected responses.

They had 41 subjects, 23 of which had diabetes. They had them lay down in a hyperbaric chamber for 60-90 minutes for between 15 and 30 sessions. Patients only performed one session per day.

Their results showed that HBO2 dropped heart rate, increased blood pressure, and significantly reduced blood glucose levels. The increase in blood pressure was more pronounced in diabetic patients and subjects with hypertension.

The reduction of blood glucose in the diabetic patients was sometimes dramatic, falling from 150 to 50 mg/dL during the hyperbaric treatment. For this reason, the authors caution using hyperbaric treatment in diabetics unless blood glucose can be continuously monitored.

The authors hypothesized that the drop in blood sugar could be due to an increase in insulin secretion, increased insulin sensitivity (due to increased tissue oxygenation), or hormonal factors that were not measured.

Other studies have found that slow breathing and HBO2 have similarities. For example, both practices decrease heart rate and blood glucose. However, slow breathing does not increase blood pressure (and sometimes lowers it) like HBO2 does. Thus, slow breathing might be a better alternative for diabetics or people with high blood pressure. We can start practicing Principle 1 today to experience many of the same benefits of HBO2, without the risk of any negative side effects (except, of course, for calm focused mind!).

Abstract from Paper

Background. We investigated the influences of hyperbaric oxygen (HBO2) on systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and blood glucose level (BGL).

Methods. Forty one patients with hypertension (HTN), diabetes mellitus (DM), HTN and DM and/or no HTN or DM underwent HBO2 sessions (15e40 sessions for each patient). SBP, DBP, HR and BGL (for diabetics) were recorded before and after each session. Results. HBO2 caused significant elevation in SBP (11%) and DBP (12%) and a decrease in HR (18%) (p <0.001). Patients with DM and HTN showed higher elevation in SBP and DBP. HBO2 lowered BGL by 23% (p <0.001). When basal BGL was in the range of 120-170 mg/dl, it dropped to <100 mg/dl in 31/60 treatment sessions (52%). When basal BGL was <120 mg/dl it dropped to <70 mg/dl in 8/34 sessions. There was a possibility of lowered BGL when basal BGL was <170 mg/dl and a marked reduction in BGL occurred when basal BGL was <120 mg/dl. HBO2 caused a marked elevation in SBP and DBP when basal SBP was >140 mmHg. Critical elevation was obtained when SBP was >160mmHg. The use of beta blockers caused significant elevation of blood pressure while reducing HR.

Conclusions. HBO2 causes elevation of blood pressure and lowering of HR and BGL, which were augmented in the presence of HTN, DM, or beta blocker. The use of beta blockers for the management of HTN should be avoided during HBO2 therapy.

Journal Reference:

Noori S. Al-Waili, Glenn J. Butler, Jorge Beale, Mahdi S. Abdullah, Michael Finkelstein, Michael Merrow, Richard Rivera, Richard Petrillo, Zev Carrey, Bok Lee, and Michael Allen, (2006) Influences of hyperbaric oxygen on blood pressure, heart rate and blood glucose levels in patients with diabetes mellitus, Archives of Medical Research, 37, 991 – 997.