Figure 1 from Optimal Nasopharyngeal Temperature Probe Placement | Semantic Scholar (2025)

During general anesthesia, the temperatures measured at the upper nasopharynx and the oropharynx, but not the nasal cavity, reflected the core temperature, therefore, the authors recommend that a probe should be placed at the naspharynx or oroph throat with mucosal attachment for accurate core temperature measurement.

It is suggested that, when nasopharyngeal temperature probes were inserted between 14 and 20 cm, they were positioned in the oropharynx or laryngopharynx, not the nasopharyx, which is customary that these probes are inserted blindly, once the endotracheal tube is placed by using directlaryngoscopy.

Any nasopharyngeal probe insertion depth between 10 and 20 cm well represents core temperature in adults having noncardiac surgery.

Nasopharyngeal thermometers accurately measure core temperature, but only when probes are inserted a proper distance, which varies with age.

This complication may have been avoided if proper technique of insertion had been used and most importantly if the practitioner had avoided the placement of any device on the operative side as confidence in the integrity of normal and abnormal tissues wanes in the settings of cancer and surgical intervention.

A rare complication involving esophageal temperature probe was reported, which was misplaced into the right intermediate bronchus and accidentally cut in a patient undergoing lobectomy of the lung.

In children with SAD insertion, TE can be accurately and feasibly measured through the SAD’s gastric channel, making it suitable for routine application.

Perfusionists should be cautious when using the nasopharyngeal site as the only surrogate of brain temperature, even in normothermic cardiac surgery because the precision of measurements is not entirely adequate.

It is imperative to continuously monitor core body temperature to detect temperature changes(hypo/hyperthermia) in order to use the device safely as chances of overheating is always present.

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It is concluded that best results are obtained when care is taken to place the thermistor in the lower quarter of the esophagus, and placing the probe by acoustic criteria cannot consistently be relied on to provide good thermometry.

The prevailing stethoscope design, with a thermistor at the tip, below the acoustic window, does not ensure placement of the thermistor within the optimal region for monitoring of core temperature, and a modification in design that would take advantage of the reliability of electrocardiographic positioning is suggested.

Intraoperative temperature monitoring is still uncommon and hence active patient warming is not a standard of care in Europe, and a European practice guideline for perioperative patient temperature management is warranted.

The weight dependence of thermoregulatory vasoconstriction was evaluated in 33 unpremedicated pediatric patients receiving isoflurane/oxygen anesthesia and caudal anesthesia with bupivacaine, and there was a good correlation between laser Doppler flowmetry and forearm-fingertip skin temperature gradients in individual patients.

Investigating the extent to which N2O/fentanyl anesthesia lowers the thermoregulatory threshold in humans found decreased skin-surface temperatures occurred primarily in the fingers, whereas the adjacent palms were largely spared, indicating that intraoperative vasoconstriction can be prevented by local neural blockade.

The oesophageal temperature recorded in the anaesthetized and intubated adult depends on the site at which it is taken and is both the warmest and the most stable.

Unintentional hypothermia is associated with myocardial ischemia, angina, and PaO2 < 80 mmHg during the early postoperative period in patients undergoing lower extremity vascular surgery.

Maintaining normothermia intraoperatively is likely to decrease the incidence of infectious complications in patients undergoing colorectal resection and to shorten their hospitalizations.

Data indicate that the intensity of vasoconstriction, once triggered, is similar during several different types of anesthesia, including isoflurane anesthesia and halothane or nitrous oxide/fentanyl anesthesia.

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