A prospective study on the precision of height data from electronic medical records in tidal volume calculation for lung-protective ventilation

Abstract

Lung-protective ventilation is now the norm for all patients, regardless of the presence of acute respiratory distress syndrome (ARDS), owing to the mortality associated with higher tidal volumes (TV). Clinicians calculate TV using recorded height from medical records and predicted body weight (PBW); however, the accuracy remains uncertain. Our study aimed to validate accurate TV settings for lung-protective ventilation by examining the correlation between the charted height and bedside measurements. In a single-center study, we compared PBW-based TV calculated from recorded height to PBW-based TV from measured height and identified factors causing height overestimation during charting. Our team measured patient height within 24 hours of admission using metal tape. TV calculated from recorded height (6–8 mL/kg PBW) was significantly larger (391.55 ± 65.98 to 522.07 ± 87.97) than measured height-based TV (162.62 ± 12.62 to 470.28 ± 89.64) (P < .01). In the height overestimated group, 57.7% were prescribed TV by healthcare provider, which was more than TV of 8 mL/kg of PBW, as determined by measured height. Negative predictors for height overestimation were male sex (OR: 0.45 [95% CI: 0.25–0.82]; P = .008) and presence of driver’s license information (OR: 0.45 [95% CI: 0.25–0.80]; P = .007), whereas Asian ethnicity was a positive predictor (OR: 4.34 [95% CI: 1.09–17.27]; P = .04). The height overestimation group had a higher in-patient mortality rate (38.5%) than the matched/underestimation group (20%) (P < .01). In stadiometer-limited hospitals, the PBW-based TV is overestimated using the recorded height instead of the measured height. In the group where heights were overestimated, over half of the patients received TV prescriptions from healthcare providers that surpassed the TV of calculated 8 mL/kg PBW based on their measured height. The risk factors for height overestimation include female sex, Asian ethnicity, and missing driver’s license data. Alternative height measurement methods should be explored to ensure precise ventilation settings and patient safety.