Effect of a Brief Educational Intervention on Endotracheal Tube Cuff Pressure

Background and rationale: Maintaining endotracheal tube cuff pressure within 20-30 cmH₂O is recommended to balance an effective tracheal seal against mucosal perfusion. In everyday practice the cuff is often inflated by palpation of the pilot balloon without manometric measurement, and pressures outside the recommended range are frequent. Low-cost educational interventions may improve adherence, but evidence from routine operating room settings is limited.

Study design and setting: This is a prospective, single-center, uncontrolled before-and-after (quasi-experimental) interventional study conducted in the operating rooms of Marmara University Pendik Training and Research Hospital, a tertiary university hospital in Istanbul, Turkey. The study was approved by the Marmara University Faculty of Medicine Clinical Research Ethics Committee; approval no: 09.2025.25-0526. Written informed consent is obtained from patients. Operating room staff are not informed that cuff pressure is being recorded during the pre-intervention period in order to avoid altering their usual practice; this approach and the anonymous collection of provider data were approved by the ethics committee. The study is reported in accordance with the TREND statement for non-randomized interventional studies.

Participants: Adult patients (≥18 years) undergoing elective surgery under general anesthesia with oral endotracheal intubation are eligible. Patients undergoing laparoscopic surgery, those receiving nitrous oxide, and those intubated with a reinforced (wire-spiral) tracheal tube were excluded, as pneumoperitoneum and nitrous oxide diffusion into the cuff are known to alter cuff pressure, and reinforced tubes differ from standard tubes in cuff design. All eligible patients during each study period are included consecutively, and the study periods were defined in advance.

Data collection: In both periods, cuff pressure is measured once, within 10 minutes after intubation and before surgical positioning, with the patient supine, using a calibrated cuff manometer (VBM Medizintechnik GmbH, Sulz am Neckar, Germany). Measurements are taken by a study investigator who is not involved in the intubation. The professional role (anesthesia technician, resident, or specialist) and years of clinical experience of the person who inflated the cuff, tube size, patient age, sex, and ASA class are recorded. If cuff pressure is outside the recommended range, it is corrected after measurement for patient safety.

Intervention. After the pre-intervention period is completed, a two-minute educational video is distributed to all anesthesia staff involved in cuff inflation via WhatsApp groups. The video explains the clinical consequences of over- and under-inflation, the recommended pressure range and the correct use of a cuff manometer. Reminder posters summarizing the same key messages are displayed in all operating rooms and remain in place throughout the post-intervention period. Post-intervention data collection begins one day after the video is distributed and follows the identical measurement protocol.

Outcomes: The primary outcome is the proportion of cuff pressure measurements within 20-30 cmH₂O compared between the pre- and post-intervention periods. The secondary outcome is the association between the cuff-inflating provider's professional role and clinical experience and cuff pressure appropriateness. Mean cuff pressure and the proportions of over-inflated (>30 cmH₂O) and under-inflated (<20 cmH₂O) measurements are reported descriptively.

Statistical analysis: Categorical variables are compared with the chi-squared or Fisher's exact test and continuous variables with the Mann-Whitney U test, as appropriate. The association of provider role and experience with appropriate cuff pressure is examined with multivariable logistic regression adjusted for study period. Because providers may contribute multiple measurements, a sensitivity analysis accounting for clustering by provider is planned. Two-sided p < 0.05 is considered statistically significant. Analyses were performed in Phyton 3.13 using pandas 3.0, SciPy 1.18 and statsmodels 0.15.