Glutamine for ITU nutrition

www.medicineteacher.blogspot.com

Functions glutamine

Glutamine becomes an essential amino acid in the human body during times of stress including critical illness and after major trauma or surgery.

Glutamine is the most abundant free amino acid in the extracellular and intracellular compartments, contributing to more than 50% of the body

’s free amino acid pool (Young 2001).

Function Cont.

Supports rapidly proliferating cells, such as lymphocytes and enterocytes
à important to immune and intestinal integrity.

Acid-base homeostasis.

Nitrogen and ammonium carrier.

Glutamine levels during illness

ICU patient mortality has been shown to be significantly higher for patients with low plasma glutamine levels

(Oudemans-van Staaten, et al. 2001).

Animal studies

Predominantly rat studies have showed that glutamine:

Limits intestinal permeability

Reduces gut atrophy

Preserves intestinal and extraintestinal IgA levels

Decreases intestinal proinflammatory cytokine production

Early human research on glutamine

Many researchers have studied replacement of glutamine, either parenterally or enterally, assuming this could lead to improved patient outcomes.

Until 2003, published trials were small: each enrolled between 35 to 84 patients.

Some studies suggested lower infection rates and perhaps improved mortality.

A meta-analysis by Novak et al. (2002) showed inconclusive results. Parenteral glutamine showed a trend towards reduced mortality as well as fewer infectious complications but no reduction in length of stay.

Enteral Glutamine

Hall et al. (2003): prospective, triple blinded study in a 10 bed ICU in Perth, Australia.

363 patients; 20g/day enteral glutamine.

No difference in: mortality at 6 months
severe sepsis
infections
consumption of inotropes.

Enteral Glutamine Cont.

Schulman et al. (2005): prospective, unblinded study involving 185 patients admitted to a surgical and trauma ICU in Charlottesville, Virginia, USA.

Patients were sequentially assigned to either standard enteral feeds or 20-40g/day glutamine supplemented feeds.

No significant difference in in-hospital mortality or secondary end points (there was a trend towards higher mortality in the glutamine group).

Why no benefit with enteral glutamine?

The proposed benefit of glutamine for human cells may also extend to bacteria.

Animal studies have demonstrated an increased growth rate of bacteria when incubated in the presence of glutamine.

(Kajikawa 2002).

Parenteral Glutamine

Dechelotte P: French study involving 114 patients in 16 ICUs.

Prospective, double-blind, controlled, randomized trial.

Received 0.5g/kg/day glutamine parenterally.

↓

infection rate: 0.45 vs 0.71 infections per patient (p <>

↓

pneumonia: 10 vs 19 patients (p <>

↓

hyperglycaemia: 20 vs 30 patients (p <>

Early death rate and 6-month survival were not different.
Survivors at 6 months: glutamine group 72%, control 83%.

Have the studies been
giving enough glutamine?

Most naturally occurring food proteins contain 4-8% of their amino acid residues as glutamine; hence, the daily consumption of glutamine is usually less than 10g. The optimal dose of glutamine is unknown

(Hall et al. 2003).

What about glutamine use
in other areas of medicine

?

Studies in:

Premature infants

Bone marrow transplants

Inflammatory bowel disease

Show similar lack of benefit.

Costs

Glutamine 10g 50ml bag

£15.96
Glutamine 20g 100ml bag £

29.60

Kabiven 9 bag

£

31.75

Last year, Ysbyty Gwynedd spent

£

12 000 on Kabiven 9.

Therefore adding 20g of glutamine would almost double the cost of enteral feeding.

Conclusions

There is insufficient evidence to conclusively determine whether glutamine supplementation for ICU patients is beneficial.

The best evidence so far indicates that there is likely to be no benefit.

The additional cost can not be justified.

References

Dechelotte P, Hasselmann M, Cynober L, et al. L-alanyl-L-glutamine dipeptide – supplemented total parenteral nutrition reduces infectious complications and glucose intolerance in critically ill patients: The French controlled, randomized, double-blind, multicenter study. Crit Care Med 2006;34:598-604.

Hall JC, Dobb G, Hall J, de Sousa R, Brennan L, McCauley R: A prospective randomized trail of enteral glutamine in critical illness 2003;29:1710-1716.

Kajikawa H, Mitsumori M, Ohmomo S: Stimulatory and inhibitory effects of protein amino acids on growth rate and efficiency of mixed ruminal bacteria. J Diary Sci 2002;85:2015-2022.

Oudemans-van Staaten HM, Bosman RJ, Treskes M, et al: Plasma glutamine depletion and patient outcome in acute ICU admissions. Intensive Care Med 2001; 27:84-90.

Novak F, Heyland DK, Avenell A, et al: Glutamine supplementation in serious illness: A systematic review of the evidence. Crit Care Med 2002; 30:2022-2029.

Schulman AS, Willcutts KF, Claridge JA, et al. Does the addition of glutamine to enteral feeds affect patient mortality?. Crit Care Med 2005 Vol. 33, No. 11.

Young VR, Ajami AM. Glutamine: The emperor or his clothes? J Nutr 2001; 131(9 Suppl):2449S-2459S.

The End. Thank you.