The implications of variations in nasal irrigation recipes in the United Kingdom

Abstract

Objective This study aims to investigate the variations in publicly available nasal irrigation recipes published in the United Kingdom (UK). Design Internet searches used to identify eligible nasal irrigation recipes. These were then examined for their physical and biochemical properties, through theoretical calculations and experimental measurement. Setting Recipes produced by healthcare providers or official national bodies in the UK. Participants No human participants. Main outcome measures Solution osmolality (classified into hypo‐, iso‐ and hypertonic), acidity (pH) and specific gravity. Results Thirteen unique recipes were identified from 17 sources. Osmolality ranged from 166.2 to 1492.2 mosmol/kg in volumes ranging from 142 to 1136 mLs (isotonic range 275‐295 mosmol/kg). Specific gravity ranged from 1.006 to 1.034. pH ranged from 7.74 to 8.11. No recipe produced a solution with isotonic properties. The majority produced hypertonic irrigations. Conclusions Most publicly available nasal irrigation recipes produce hypertonic solutions but there is great variability in the osmolality and volume. UK organisations should take action to review published recipes to bring these into alignment with latest guidelines (recommending against hypertonic saline use) and reduce variability in patient interpretations.

Do variations in nasal irrigation recipes and storage effect the risk of bacterial contamination?

“…Although not a common additive, 10 sugar is advocated by some to improve the taste of saline irrigation and therefore the patient compliance. Our study suggests that sugar has no greater effect on bacterial growth in stored nasal irrigation solution beyond a standard salt and bicarbonate of soda solution (within 12 days).…”

“…These recipes reflect the most commonly cited make-at-home recipes publicly available, including as advised by the National Health Service online. 10…”

“…These recipes reflect the most commonly cited make-at-home recipes publicly available, including as advised by the National Health Service online. 10 All solutions were mixed in a typical kitchen environment (clean, freshly washed measuring jug) and transported to the testing laboratory in sterilised containers (plastic bottles). Containers were sterilised using a sterilising solution typically used in home food and drink production (Star San Acid Sanitiser, Denver, USA).…”

“…None of these produce an isotonic solution (as recommend by the European Position Paper on Rhinosinusitis and Nasal Polyps). 1,10 All solutions produce hypertonic solutions (331.4 mosmol/l, 532.6 mosmol/l and 550.5 mosmol/l, respectively), with solution 1 producing the closest to an isotonic solution. The effects of osmolality of a solution of bacterial growth has been researched previously, with other hyperosmolar agents (such as honey) being advocated in management of biofilms as they effect the water regulation of microbiomes.…”

“…These recommend varying quantities of salt (sodium chloride), bicarbonate of soda and sugar (largely sucrose) in varying volumes of water. 10 Practically, many patients will not make a new nasal irrigation solution for every use, and many will store a pre-made volume of solution over a short period of time.…”