Effect of hyperbaric oxygen on the growth and susceptibility of facultatively anaerobic bacteria and bacteria with oxidative metabolism to selected antibiotics

Abstract

Wild strains of Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis were tested in an experimental hyperbaric chamber to determine the possible effect of hyperbaric oxygen on the susceptibility of these strains to the antibiotics ampicillin, ampicillin + sulbactam, cefazolin, cefuroxime, cefoxitin, gentamicin, sulfamethoxazole + trimethoprim, colistin, oxolinic acid, ofloxacin, tetracycline, and aztreonam during their cultivation at 23 °C and 36.5 °C. Ninety-six-well inoculated microplates with tested antibiotics in Mueller–Hinton broth were cultured under standard incubator conditions (normobaric normoxia) for 24 h or in an experimental hyperbaric chamber (HAUX, Germany) for 24 h at 2.8 ATA of 100% oxygen (hyperbaric hyperoxia). The hyperbaric chamber was pressurised with pure oxygen (100%). Both cultures (normoxic and hyperoxic) were carried out at 23 °C and 36.5 °C to study the possible effect of the cultivation temperature. No significant differences were observed between 23 and 36.5 °C cultivation with or without the 2-h lag phase in Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis. Cultivation in a hyperbaric chamber at 23 °C and 36.5 °C with or without a 2-h lag phase did not produce significant changes in the minimum inhibitory concentration (MIC) of Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis. For the tested strains of Pseudomonas aeruginosa, the possible effect of hyperbaric oxygen on their antibiotic sensitivity could not be detected because the growth of these bacteria was completely inhibited by 100% hyperbaric oxygen at 2.8 ATA under all hyperbaric conditions tested at 23 °C and 36.5 °C. Subsequent tests with wild strains of pseudomonads, burkholderias, and stenotrophomonads not only confirmed the fact that these bacteria stop growing under hyperbaric conditions at a pressure of 2.8 ATA of 100% oxygen but also indicated that inhibition of growth of these bacteria under hyperbaric conditions is reversible.

Reactive Oxygen Species (ROS)-Mediated Antibacterial Oxidative Therapies: Available Methods to Generate ROS and a Novel Option Proposal

“…Anyway, HBOT did not show any additive or synergistic effect with other antimicrobial agents, such as distamycin and rifampicin [57]. Very recently, it has been reported that wild strains of Pseudomonads, Burkholderias, and Stenotrophomonads stopped growing under hyperbaric conditions at a pressure of 2.8 ATA of 100% oxygen [230]. HBOT is used as a primary or alternative method for the treatment of infections such as diabetic foot infection, surgical site infections, gas gangrenes, osteomyelitis, and necrotizing compartments [229].…”

“…Moreover, HBOT potentiates the antibacterial effects of some antibiotics such as imipenem and tobramycin (Figure 6). Hyperoxia (98% O2 at 2.8 absolute ATA-approximately 284.6 kPa) has been shown to enhance the effect of nitrofurantoin, sulfamethoxazole, trimethoprim, gentamicin, and tobramycin in E. coli strains (serotype 018 and ATCC 25922) [230]. Two works by Kolpen et al report that the combination therapy of ciprofloxacin and HBOT may be potentially beneficial for the eradication of infections caused by the biofilm forming P. aeruginosa [231,232].…”

Accidental Aluminum Phosphide Intoxication Successfully Treated with Hyperbaric Oxygen Therapy: A Case Report

“…HBOT has become the standard treatment for severe carbon monoxide poisoning, decompression illness (DCI), cerebral artery gas embolism, sudden sensorineural hearing loss (SSNHL), delayed radiation necrosis, infected wounds, especially for deep and chronic infections such as osteomyelitis, necrotizing soft tissue infections, and diabetic foot infections [ 18 , 19 ].…”