The values below pertain to a patient who is being mechanically ventilated with a measured exhaled tidal volume (Vᴛ)of 700 mL.
$\begin{array} { | l | l | l | }
\hline \text { Time } & \text { Peal Inspiratary Presure (ㄴ } \mathrm { H } _ { \mathbf { 2 } } \mathbf { 0 } \text { ) } & \text { Plateau Prefure (cm } \left. \mathrm { H } _ { 2 } \mathbf { O } \right) \
\hline 0800 & 35 & 30 \
\hline 1000 & 39 & 34 \
\hline 1100 & 45 & 39 \
\hline 1130 & 50 & 44 \
\hline
\end{array}$
Analysis of this data points to which of the following conclusions?
A) Airway resistance is increasing.
B) Airway resistance is decreasing.
C) Lung compliance is increasing.
D) Lung compliance is decreasing.

Question

The values below pertain to a patient who is being mechanically ventilated with a measured exhaled tidal volume (Vᴛ)of 700 mL.
$\begin{array} { | l | l | l | } 
\hline \text { Time } & \text { Peal Inspiratary Presure (ㄴ } \mathrm { H } _ { \mathbf { 2 } } \mathbf { 0 } \text { ) } & \text { Plateau Prefure (cm } \left. \mathrm { H } _ { 2 } \mathbf { O } \right) \
\hline 0800 & 35 & 30 \
\hline 1000 & 39 & 34 \
\hline 1100 & 45 & 39 \
\hline 1130 & 50 & 44 \
\hline
\end{array}$
Analysis of this data points to which of the following conclusions?
A) Airway resistance is increasing.
B) Airway resistance is decreasing.
C) Lung compliance is increasing.
D) Lung compliance is decreasing.

Quizplus · Accepted Answer

To evaluate this information the transairway pressure (Pᴛᴀ)is calculated for the different times: 0800 Pᴛᴀ = 5 cm H₂O,1000 Pᴛᴀ = 5 cm H₂O,1100 Pᴛᴀ = 6 cm H₂O,and 1130 Pᴛᴀ = 6 cm H₂O.This data shows that there is no significant increase or decrease in this patient's airway resistance.Analysis of the patient's plateau pressure (Pₚₗₐₜₑₐᵤ)reveals an increase of 15 cm H₂O over the three and a half hour time period.This is directly related to a decrease in lung compliance.Calculation of the lung compliance (CS = Vᴛ/(Pₚₗₐₜₑₐᵤ - EEP)at each time interval reveals a steady decrease from 20 mL/cm H₂O to 14 mL/cm H₂O.

The Values Below Pertain to a Patient Who Is Being