Validation of two preoxygenation techniques, 3 min tidal volume breath and eight vital capacity breath techniques in tribal and non-tribal population of Eastern India

Abstract

Background: Preoxygenation during anesthesia can be done by 3 min tidal volume breath and eight vital capacity breath in 1 min, conventionally. Population of our country is not homogenous. Aims and Objectives: The present study was conducted to validate preoxygenation processes in people of eastern India. Materials and Methods: Total 140 patients of ASA grade I and II, age group 20–50 posted for surgeries under GA were allotted in TV and VC group. Every odd number and even number patient was tested for TV method and VC method, respectively, with a Magill circuit and airtight face mask with 100% oxygen flow at a rate of 10 L/min. Time and number of breaths were noted when end tidal oxygen concentration ≥90% in TV and VC group, respectively. Results: In TV method, the mean time (in minute) was 3.10±0.27 and 3.13±0.24 for tribal and non-tribal sub-group (P=0.80); 3.02±0.37 and 3.10±0.27 for tribal and non-tribal male (P=0.57); and 3.18±0.05 and 3.16±0.21 for tribal and non-tribal female (P=0.57). In VC method, mean number of VC breaths was 8.32±0.60 and 8.43±0.74 for tribal and non-tribal sub-group (P=0.76); 8.75±0.49 and 8.23±0.70 for tribal and non-tribal male (P=0.42); and 8.20±0.60 and 8.60±0.72 for tribal and non-tribal female (P=0.16). Patients completing preoxygenation in TV and VC method – tribal: 22% and 53%, non-tribal: 4% and 62%, tribal male: 22% and 20%, non-tribal male: 8% and 68%, tribal female: 0% and 60%, and non-tribal female: 0 and 57%, respectively. Conclusion: No significant difference found between tribal and non-tribal groups of both sexes in each method. Completion of preoxygenation was higher in VC group, though not tested statistically.

Keywords

• preoxygenation; tidal volume; vital capacity; tribal; non-tribal