New Tool Predicts Need for Invasive Ventilation in Flu-Related Pneumonia

Researchers in Beijing have announced the development of a novel assessment tool, the Flu-IV Score, which predicts the need for invasive mechanical ventilation (IMV) in patients with influenza-related pneumonia (Flu-P) within 14 days of admission. The results of their multicenter study, conducted in in 5 tertiary hospitals in China, was recently published in BMC Pulmonary Medicine.

In the current study, 1107 patients with confirmed Flu-P were enrolled retrospectively from January 2012 to December 2019, including 895 patients in a derivation group and 212 patients in a validation group. Enrolled patients had a median age of 61 years and were 54.5% (603/1107) male. The most common comorbidities were cardiovascular disease (22.7%; 251/1107), diabetes mellitus (13.4%; 148/1107), and cerebrovascular disease (10.3%; 114/1107).

The predictive model was based on independent risk factors for IMV in the patients in the derivation cohort. Participants in the derivation cohort were divided into 2 groups based on whether they had undergone IMV within 14 days after admission. The researchers compared baseline characteristics between these 2 patient groups. The investigators incorporated all variables that produced a P <.1 in the first univariable analyses into a multivariable, backward stepwise logistic regression model to identify the risk factors related to 14-day IMV rates (which included age ≥65 years, influenza A virus infection, existence of solid malignant tumors, respiratory rate ≥30 breaths per minute, leukocyte count >10 × 109/L, leukocytes <0.8 × 10⁹/L, albumin <35 g/L, arterial pH <7.35, ratio of partial pressure of oxygen in arterial blood to inspired oxygen fraction [PaO₂/FiO_2] <300 mmHg, early neuraminidase inhibitor [NAI] therapy, and systemic corticosteroids use at admission).

A total of 10.6% (117/1107) of participants required IMV within 14 days of admission. The authors used a cumulative score of 5 points to identify patients at risk of IMV. Multivariate regression analyses showed that the most common factors associated with IMV included early NAI use (odds ratio [OR] 0.014; 95% CI, 0.003-0.083; P <.001; -3 points), lymphocytes <0.8 × 10⁹/L (OR 5.755; 95% CI, 2.261-14.649; P <.001; 1 point), multilobar infiltrates (OR 4.568; 95% CI, 1.591-13.118; P =.007; 1 point), systemic corticosteroid use (OR 5.874; 95% CI, 2.356-14.642; P <.001; 1 point), age ≥ 65 years (OR 9.052; 95% CI, 3.544-23.119; P <.001; 1 point), PaO₂/FiO₂<300 mmHg (OR 9.966; 95% CI, 3.619-27.447; P <.001; 2 points), respiratory rate ≥30 breaths per minute (OR 53.835; 95% CI, 19.711-147.033; P <.001; 3 points), and arterial pH <7.35 (OR 255.404; 95% CI, 42.701-527.608; P <.001; 4 points).

The Flu-IV Score had a sensitivity of 85.5% and a specificity of 88.8%. It showed better predictive performance than the ratio of oxygen saturation (ROX) index (area under the receiver operating characteristic curve [AUROC] = 0.909 vs 0.594; P =.004), modified ROX index (AUROC = 0.909 vs 0.633; P =.012), and heart rate, acidosis, state of consciousness, oxygenation, and respiratory rate (HACOR) scale (AUROC = 0.909 vs 0.622, P <.001) using the validation cohort.

Reference

Chen L, Han X, Li Y, Zhang C, Xing X. Flu-IV score: a predictive tool for assessing the risk of invasive mechanical ventilation in patients with influenza-related pneumonia. BMC Pulm Med. 2022;22(1):47. doi:10.1186/s12890-022-01833-2

New Tool Predicts Need for Invasive Ventilation in Flu-Related Pneumonia

Reference

Want to read more?

Want to read more?