Mendelson's syndrome, named in 1946 for American obstetrician and cardiologist
Curtis Lester Mendelson
Curtis Lester Mendelson (September 4, 1913 - October 13, 2002) was an obstetrician and American cardiologist.
Mendelson's syndrome
Mendelson's syndrome, named in 1946 for American obstetrician and cardiologist Curtis Lester Mendelson, is a fo ...
, is a form of
chemical pneumonitis or
aspiration pneumonitis
Aspiration pneumonia is a type of pneumonia, lung infection that is due to a relatively large amount of material from the stomach or mouth entering the lungs. Signs and symptoms often include fever and cough of relatively rapid onset. Complication ...
caused by
aspiration of stomach contents (principally gastric acid) during
anaesthesia in
childbirth. This complication of anaesthesia led, in part, to the longstanding ''
nil per os'' (abbr. NPO; a Latin phrase meaning nothing by mouth) recommendation for women in labour.
Presentation
Mendelson's syndrome is characterised by a
bronchopulmonary reaction following aspiration of gastric contents during general anaesthesia due to abolition of the
laryngeal reflexes. The main clinical features are signs of general
hypoxia
Hypoxia means a lower than normal level of oxygen, and may refer to:
Reduced or insufficient oxygen
* Hypoxia (environmental), abnormally low oxygen content of the specific environment
* Hypoxia (medical), abnormally low level of oxygen in the tis ...
, two to five hours after anaesthesia. Such features may include cyanosis, dyspnea, fever, pulmonary wheeze, crepitant rales, rhonchi, and
tachycardia with a low blood pressure. Decreased
arterial oxygen tension
Blood gas tension refers to the partial pressure of gases in blood. There are several significant purposes for measuring gas tension. The most common gas tensions measured are oxygen tension (PxO2), carbon dioxide tension (PxCO2) and carbon monoxi ...
is also likely to be evident.
Pulmonary edema can cause sudden death or death may occur later from pulmonary complications.
Risk factors
Historically it is said that a patient is at risk if they have:
* Residual gastric volume of greater than 25ml, with
*
pH of less than 2.5
However these are indirect measurements and are not factors that directly influence aspiration risk.
[
Patients with a high risk should have a rapid sequence induction. High risk is defined as these factors:][
# Non-elective surgical procedure
# Light anaesthesia/unexpected response to stimulation
# Acute or chronic, upper or lower GI pathology
# Obesity
# Opioid medication
# Neurological disease, impaired conscious level, or sedation
# Lithotomy position
# Difficult intubation/airway
# Gastrointestinal reflux
# Hiatal hernia
]
Eponym
It is named for Curtis Mendelson.
References
External links
*
{{Respiratory pathology
Syndromes affecting the respiratory system
Pneumonia
Health issues in pregnancy