Case Study
Sandra and Bob boarded their first European trip since Bob’s retirement, starting with London. During the 8-hour flight, Bob slept while Sandra read, and he gave her extra space in their seats. After landing, Sandra struggled to breathe, and Bob gave her an inhaler, suspecting an asthma attack. Later, at the hotel, she experienced chest pain radiating to her left arm and severe shortness of breath, prompting Bob to call for help.
At the hospital, Sandra’s vitals showed pulse 102 bpm, BP 90/56, and swelling in her right leg. She received oxygen, monitoring, and an initial assessment by the ER team. Blood tests indicated the need for further imaging. The doctor ordered a CT scan, ultrasounds of both legs, and a V/Q scan to confirm the diagnosis and guide treatment.
Respiratory vs Cardiovascular Symptoms
In Sandra’s case, signs of a respiratory problem include wheezing, which suggests airway narrowing commonly seen in asthma. Shortness of breath indicates respiratory distress and difficulty in breathing. Furthermore, left-sided chest discomfort may indicate decreased oxygen flow to the heart, which can occur in respiratory illnesses such as asthma or during a cardiac event. These respiratory symptoms collectively point toward a potential respiratory issue affecting Sandra.
Signs and Symptoms of Cardiovascular System Problems
Sandra’s case also presents signs that could indicate a cardiovascular system problem. The radiating pain in the left arm is a significant symptom often associated with heart-related issues such as angina or a heart attack. Furthermore, leg swelling suggests poor circulation and fluid retention, which are commonly seen in cardiovascular conditions like congestive heart failure. These cardiovascular symptoms raise concerns regarding Sandra’s heart health and the need for further evaluation and diagnosis.
Relationship Between Breathing Rate, Blood pH, and PCO2
An increased breathing rate (tachypnea) helps to compensate for reduced oxygen and increased carbon dioxide (CO2) levels. Asthma and other respiratory diseases can cause respiratory acidosis, which is defined by low blood pH due to increased CO2 levels. PCO2 is the partial pressure of carbon dioxide, and it can be raised in disorders such as asthma, where poor gas exchange results in CO2 accumulation (Dharmage et al., 2019). Sandra’s blood pressure is lower than usual at 90/56, which might be attributed to decreased cardiac output caused by cardiovascular disease.
A computed tomography (CT) scan of the legs is necessary to evaluate blood flow and ventilation-perfusion matching (Dharmage et al., 2019). The presence of leg swelling, notably if worse in the right leg, raises concerns about deep vein thrombosis (DVT) or pulmonary embolism (PE). These imaging tests help confirm or rule out these conditions.
Effects of Asthma on Blood CO2 and pH
In asthma, airway constriction leads to increased resistance to airflow, resulting in inadequate elimination of CO2 during exhalation. This CO2 buildup in the blood can lead to respiratory acidosis, a disease characterized by low blood pH (Betts et al., 2022). Excess CO2 combines with water to form carbonic acid, lowering the pH. The body compensates for respiratory acidosis by increasing breathing to expel CO2 and restore normal blood pH. However, if asthma symptoms persist, the compensatory mechanism may be insufficient to normalize the blood pH fully.
Reference
Dharmage, S. C., Perret, J. L., & Custovic, A. (2019). Epidemiology of asthma in children and adults. Frontiers in Pediatrics, 7. Web.
Betts, J. G., Desaix, P., Johnson, E., Johnson, J. E., Korol, O., Kruse, D., Poe, B., Wise, J., Womble, M. D., & Young, K. A. (2022). Anatomy and physiology. OpenStax, Rice University.