Children who plague parents have a cough after a cold: it is often the drip (flow) behind the nose that is at work

China Shandong Network - Perception Shandong January 17 news (correspondent Li Chengxiu Ma Jin) The baby has a cold, it is difficult to survive the fever period of 3-5 days, just want to relax, but the cough that follows may quickly "destroy" the tight nerves of parents and become one of the reasons that plague parents and lead to repeated visits. Some children can get better on their own within 5-7 days, but some children can last for 1-2 weeks or more, and what is more headache is that the baby has taken a lot of anti-inflammatory drugs and cough medicines and still does not get better. So, what are the main causes of your child's cough after a cold? Today, Xin Yi, director of the Children's Intensive Care Unit of Yantai Yuhuangding Hospital, talked to you about the most likely "culprit" - retronasal drip (flow) syndrome, which is colloquially known as "nasal reflux".

What is cough? Why cough?

Cough can be divided into autonomous cough and involuntary cough. As the name suggests, autonomous cough is an active, subjective action and sound, with a clear purpose. Non-autonomous cough is not under our subjective control, and we usually refer to cough as involuntary cough. Non-self-contained cough is a defensive reflex of the body that aims to remove harmful factors from the respiratory tract, such as sputum, inhaled/choked foreign bodies, etc. In order to complete a cough reflex, the receptors present in our respiratory tract (such as some cough receptors, etc.) are stimulated, and the information is transmitted to the brain through the vagus nerve (the highway that transmits information), and then the instructions are issued to the trachea, lungs and other effector organs to complete the coughing action. Therefore, whether the root cause of cough is that the receptor site and the part containing the vagus nerve are stimulated, when these receptors and nerves are rich, including the back of the nose, pharynx, larynx, trachea, bronchial tube, external auditory canal, etc., inflammation, temperature changes and environmental irritations such as cold, soot, dust mites, etc. can cause cough.

What happens in the later stages of a cold in children?

When a cold occurs, the pathogen (bacteria or viruses, etc.) first invades the upper respiratory tract (nose, pharynx, larynx) inflammation occurs, often manifested as fever, runny nose, nasal congestion, hoarseness, etc., as our body's immunity fights with the pathogen, after 3-5 days can defeat the pathogen, the result is cleared, but the nasopharyngeal inflammation may still exist, it takes a period of time to recover, and the nasopharyngeal mucosa where inflammation occurs will become more sensitive, the response to stimuli such as ambient temperature will be enhanced, and the secretions will increase (nasal discharge), Due to the swelling of the nasal mucosa, the nasal discharge is not easy to discharge, it will "reverse" into the nasopharynx, larynx and even the trachea, causing irritating cough, which is called "postnasal drainage syndrome (PNDS)", professionally known as "upper airway cough syndrome (UACS)", which is the main cause of cough after a cold in children. Of course, the diagnosis of retronasal drip syndrome requires the exclusion of lower respiratory tract diseases with tracheitis, bronchitis, and even pneumonia.

Xin Yi (first from the right) examines the child's body

Retronasal drip (flow) leads to characteristic manifestations of cough

Retronasal drip (flow) i.e. nasal discharge is an irritating cough caused by the backflow of secretions through the posterior nostril orifice to the pharynx, as shown in Figure 1. Clinical features include: cough in the early morning or after the change of position and activity is obvious, some children at night before falling asleep, midnight or early in the morning, often cough dozens of times, cough out or swallow "sputum" can be relieved, severely affect sleep; obvious "nasal sound" when speaking, sleep can hear "nasopharyngeal purring" or "snoring", nasal congestion can appear when the mouth breathes; older children can complain of nasopharyngeal dryness, foreign body sensation, can be repeatedly "throat clearing", cough frequently can be accompanied by headache discomfort Physical examination can find secretions in the nasal cavity and posterior pharynx; often respond well to nasal mucosal congestion relievers, nasal corticosteroids and antihistamines, etc., and can reduce symptoms after 3-5 days of application, and if the relief is not obvious, other causes need to be further investigated.

Xin Yi (first from left) and his medical team discuss the patient's condition

Treatment of retronasal drip (flow) syndrome

Because the cough caused by postnasal drip (flow) is secondary, some children can recover on their own with the absorption of nasopharyngeal inflammation, as long as this part of the children do not affect sleep and daily learning, they do not need drug treatment, and keep the nasal secretions can be discharged in time. If the child's cough is obvious, especially if the night attacks are frequent and the quality of sleep is affected, it can usually be used: nasal irrigation: elderly children can use nasal irrigation with sea saline and other preparations to promote the adequate drainage of nasal secretions and the absorption of nasopharyngeal mucosa inflammation; for children in small age groups, it is not recommended for non-professional parents. Topical nasal spraying: topical spraying of nasal mucosal congestion relievers such as propranolamine nasal sprays and nasal corticosteroids such as mometasone furoate nasal sprays for short-term (no more than 1 week) may be used in combination, nasal mucosal congestion relievers are not recommended for children in small age groups. Oral antihistamines: eg, loratadine, can be used in combination with nasal spraying in children with frequent coughs, especially in children with early morning attacks, environmental cold allergies, or allergic rhinitis based on the state. Children in the small age group of less than 2 years old are not recommended for drug treatment unless the cough is significant and other causes are excluded, and measures such as keeping warm, strengthening nursing, and using devices such as nasal suction devices to clean nasal secretions in a timely manner can often be relieved in about 1 week.

Children's cough after a cold is very common, often the use of a variety of antibacterial drugs and cough drugs are ineffective, so that parents are troubled, distressed, bad mood, and the culprit behind it is often the postnasal drip (flow), if parents can identify and seek medical treatment as soon as possible or take appropriate measures, can significantly reduce symptoms and shorten the cough time course, so that the baby recovers as soon as possible.