Ultrasound Assessment Of Diaphragmatic Function During Acute Exacerbation Of Chronic Obstructive Pulmonary Disease: A Pilot Study

Figures & data

Figure 1 Right diaphragm thickness on B-mode ultrasonography.

Table 1 Characteristics Of The Study Population

Characteristics	N = 10
Age, years	79.8 ± 8.1
Sex (male)	10/10 (100%)
Length of hospital stay, days	7.6 ± 3.3
Height	1.66 ± 0.04
Weight	60.9 ± 10.4
BMI	22.3 ± 3.8
FEV1, liters (predicted %)	55.8 ± 25.5 (55.8%)
FVC, liters (predicted %)	79.1 ± 22.1 (79.1%)
FEV1/FVC, %	44.8 ± 12.6
RV, liters	2.3 ± 0.2
TLC, liters	5.2 ± 0.6
SGRQ, symptom	43.0 ± 21.9
SGRQ, activity	65.5 ± 21.1
SGRQ, impact	32.7 ± 15.9
SGRQ, total	44.7 ± 14.9

Abbreviations: BMI, body mass index; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; RV, residual volume; TLC, total lung capacity; SGRQ, St. George’s Respiratory Questionnaire.

Table 2 Ultrasound Parameters For Diaphragmatic Function

	Initial	Follow-Up	p-value
TF, right	80.1 ± 104.9	159.5 ± 224.6	0.011
TF, left	81.9 ± 53.2	126.8 ± 125.8	0.173
Excursion, right (cm)	2.2 ± 0.6	2.3 ± 1.2	0.753
Excursion, left (cm)	1.4 ± 0.6	1.5 ± 0.6	0.345

Abbreviation: TF, thickening fraction.

Table 3 Pulmonary Function Test Variables In Correlation With Diaphragmatic Function

	FEV1, Liters	FEV1, Predicted %	FVC, Liters	FVC, Predicted %
Initial (during exacerbation phase)
TF, right	0.289 (0.450)	0.438 (0.238)	0.086 (0.827)	0.166 (0.669)
TF, left	0.362 (0.338)	0.309 (0.419)	0.082 (0.834)	0.112 (0.774)
Excursion, right (cm)	0.430 (0.395)	0.010 (0.985)	0.586 (0.222)	0.199 (0.706)
Excursion, left (cm)	0.438 (0.385)	0.357 (0.488)	0.905 (0.013)^a	0.814 (0.049)^a
Follow-up (during stable phase)
TF, right	0.512 (0.159)	0.892 (0.017)^a	0.394 (0.294)	0.495 (0.175)
TF, left	0.687 (0.041)^a	0.744 (0.022)^a	0.441 (0.234)	0.388 (0.303)
Excursion, right (cm)	0.206 (0.696)	0.293 (0.573)	0.584 (0.224)	0.100 (0.850)
Excursion, left (cm)	0.564 (0.244)	0.308 (0.552)	0.856 (0.030)^a	0.615 (0.194)

Notes: Values are expressed as correlation coefficient, r value (p-value); ^ap < 0.05.

Abbreviations: FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; TF, thickening fraction.

Figure 2 Linear correlation between the change in diaphragmatic excursion on the right and (A) time to subsequent exacerbation and (B) time taken to recover from the exacerbation.