|Year : 2023 | Volume
| Issue : 1 | Page : 1
Chronic obstructive pulmonary disease and the diaphragm
Department of Respiratory Medicine, Apollo Hospitals, Chennai, Tamil Nadu, India
|Date of Submission||04-Apr-2023|
|Date of Acceptance||05-Apr-2023|
|Date of Web Publication||29-Apr-2023|
Dr. R Narasimhan
Apollo Hospitals, Chennai, Tamil Nadu
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Narasimhan R. Chronic obstructive pulmonary disease and the diaphragm. J Assoc Pulmonologist Tamilnadu 2023;6:1
Chronic obstructive pulmonary disease (COPD) is a systemic disease with special effects on the respiratory system. Respiratory pump failure is the hallmark of COPD. The respiratory pump includes the intercostals and diaphragm. We all know that COPD is caused by both smoking and toxic gases inhalation. It is a limiting respiratory disease with high morbidity and mortality. Dyspnea and exercise limitation are affected by COPD and are associated with a reduced quality of life. In severe COPD, respiratory muscles suffer the most and when we have a patient with type 2 respiratory failure with high pCO2 levels, indiscriminate use of sedatives and paralytic agents could delay the process of weaning. COPD causes hyperinflation of the lungs and imposes a heavy burden on the inspiratory muscles. This is the cause of dyspnea and exercise intolerance. The situation is akin to an inflated balloon, where further pushing of air into the balloon will not result in any increase in the size of the balloon.
Diaphragm performance is mainly characterized by strength and endurance. Strength is defined as the capacity of the muscle to generate force. Endurance is defined as the muscle to maintain and sustain some for a certain force for a certain period. In other words, this defines what we call in the intensive care unit as muscle fatigue or pump failure which is identified by the raised pCO2 levels, although oxygen levels can be normal. Loss of strength and endurance results in diaphragm weakness and decreased performance. This flattens the diaphragm curve.
These Respiratory muscles diaphragm and intercostal muscles have to be kept in mind when one managing a COPD patient with respiratory failure. Decision on oxygen support, noninvasive ventilation, or bilevel positive airway pressure has to be addressed and discussed with the critical care team. If the decision on intubation is taken, it is preferable to avoid respiratory paralysants and use a generous dose of sedatives to intubate. This is due to the reason that the diaphragm is the last to recover, and in severe COPD patients, it is the respiratory pump failure that includes the diaphragm and intercostals that are at fault. This happens due to two reasons. One is the overstretched inspiratory muscles, and the second, the persistent hypoxia itself, can cause respiratory muscle fatigue.
If a tracheostomy has to be done for a patient with severe COPD, all the above-mentioned factors will come into play. A multidisciplinary team consisting of a pulmonologist, critical care physician, ear, nose, and throat surgeon, and physiotherapist is a necessity if the patient has to come out of the ventilator and tracheostomy.
| References|| |
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