Auscultation

General Description

Auscultation is part of the physical examination in most routine medical check-ups or evaluations to assess symptoms and detect disease. During this diagnostic procedure, the specialist listens to body sounds using a stethoscope, also known as a phonendoscope, a device that amplifies sounds to facilitate auscultation.

Depending on the organs examined, auscultation can be of several types:

• Pulmonary auscultation: evaluates respiratory function and may detect:
• Wheezes (high-pitched sounds): a sign of airway obstruction.
• Crackles (rales): indicate fluid accumulation in the lungs.
• Rhonchi (low-pitched sounds): suggest abnormal airway secretions.
• Breath sounds (murmurs): it is normal to hear air entering the alveoli, producing a soft sound. If absent or markedly diminished, it may indicate alveolar obstruction.
• Pleural friction rub: occurs when the visceral and parietal pleura rub against each other instead of sliding smoothly due to inflammation. It is heard similarly to the creaking of leather.
• Cardiac auscultation: assesses heart function. It is based on listening to the sounds generated by valve opening and closure, as well as blood flow. It is used to determine whether there are:
• Murmurs: produce a harsh or blowing sound during the heartbeat due to turbulent blood flow across valves.
• Arrhythmias: the heart may beat too fast (tachycardia), too slowly (bradycardia), or irregularly. These abnormalities are detected by hearing more or fewer beats than normal.
• Intestinal or digestive auscultation: involves listening to bowel sounds, typically described as gurgling or irregular clicking. Variations may indicate pathology:
• Loud gurgling (borborygmi): caused by the movement of gas within the intestines. When pronounced, they may indicate gastroenteritis or early intestinal obstruction.
• Tinkling sounds: suggest the presence of both air and fluid, possibly due to obstruction.
• Decreased bowel sounds: usually indicative of peritonitis, severe constipation, or the effect of certain medications such as codeine or antispasmodics.
• Fetal auscultation: detects fetal heartbeats within the uterus. In these cases, a Pinard stethoscope is used, a specialized device placed on the mother’s abdomen.

When is it indicated?

Auscultation is one of the basic procedures used to assess a patient’s health status. Regardless of symptoms, this examination provides useful information to detect or rule out pulmonary, cardiac, or digestive diseases. Abnormal findings often require confirmation with complementary tests.

Some of the conditions diagnosed with the aid of auscultation include: bronchitis, bronchiolitis, chronic obstructive pulmonary disease (COPD), pneumonia, respiratory failure, pulmonary emphysema, mitral valve disease, heart failure, atrial fibrillation, intestinal obstruction, and peritonitis.

How is it performed?

To perform auscultation, the patient exposes the chest and sits (pulmonary and cardiac auscultation) or lies down (intestinal or fetal auscultation) on the examination table. During the procedure, the patient must remain silent and maintain a normal respiratory rate unless otherwise instructed. The specialist places the stethoscope earpieces in both ears and presses the diaphragm against the skin at predetermined auscultation sites:

• Cardiac auscultation: five sites:
• Aortic: second right intercostal space.
• Pulmonic: second left intercostal space.
• Erb’s point (secondary pulmonic): third left intercostal space.
• Tricuspid: fourth left intercostal space.
• Mitral or apical: fifth left intercostal space or cardiac apex.
• Pulmonary auscultation: eight sites:
• Right upper zone: apex of the right lung.
• Right mid zone: upper lobe of the right lung.
• Right axilla: middle lobe of the right lung.
• Right lower zone: lower lobe of the right lung.
• Left upper zone: apex of the left lung.
• Left mid zone: upper lobe of the left lung.
• Left axilla: left upper lobe.
• Left lower zone: lower lobe of the left lung.
• Digestive auscultation: bowel sounds are assessed in the eight abdominal quadrants:
• Right hypochondrium: gallbladder, right lobe of the liver, upper pole of the right kidney, hepatic flexure of the colon.
• Epigastrium: stomach, duodenum, pancreas.
• Left hypochondrium: spleen, upper pole of the left kidney, splenic flexure of the colon, gastric fundus (upper part of the stomach).
• Right flank: lower pole of the right kidney, ascending colon, duodenum, jejunum.
• Mesogastrium: transverse colon, small intestine, aorta.
• Left flank: lower pole of the left kidney, descending colon.
• Right iliac fossa: cecum, appendix, right ureter.
• Hypogastrium: pelvis, bladder.
• Left iliac fossa: sigmoid colon, left ureter.
• Fetal auscultation: the fetal heart forms in the sixth week of gestation and can be heard with a Pinard stethoscope from the twentieth week onward. The fetal head and back are the areas where the heartbeat is best detected; therefore, auscultation is combined with ultrasound to determine fetal position.

Risks

Auscultation poses no risk to the patient.

What to expect from an auscultation

Auscultation is a test that lasts only a few minutes and can be performed in a clinical setting. Once completed, normal activities can be resumed without the need for rest.

To ensure proper sound detection, the patient must be bare from the waist up, and both the patient and any companions should remain silent. Typically, the patient sits on the examination table for pulmonary or cardiac auscultation and lies down for digestive or fetal auscultation.

Results are obtained immediately after the procedure. The specialist may request additional tests to confirm clinical suspicion.

Specialties in which auscultation is requested

Auscultation is used across many medical specialties to aid in diagnosis or assess the patient’s overall health status. These include Family and community medicine, Pediatrics, Cardiology, Pulmonology, General and digestive system surgery, Palliative care, Complementary medicine, Gynecology and Obstetrics, and Medical oncology.