The Effect of Povidone-iodine Ophthalmic Surgical Prep Solution on Respiration in Children Undergoing Strabismus Surgery With General Anesthesia.

The Effect of Povidone-iodine Ophthalmic Surgical Prep Solution on Respiration in Children Undergoing Strabismus Surgery With General Anesthesia.

The Effect of Povidone-iodine Ophthalmic Surgical Prep Solution on Respiration in Children Undergoing Strabismus Surgery With General Anesthesia.

Determine whether the application of povidone-iodine ophthalmic solution onto the ocular surface causes a change in respiration in children undergoing strabismus surgery with general anesthesia. Hypothesis: The application of povidone-iodine ophthalmic solution to the ocular surface causes a change in respiration in children during general anesthesia prior to strabismus surgery.

The study is randomized and single blind. One hundred children were randomly assigned to have either povidone-iodine (group A) or balanced salt solution (BSS) (group B) eye drops instilled into their eyes during anesthesia just prior to strabismus surgery. After induction of anesthesia and insertion of an LMA while the patient was at a steady state of anesthesia and spontaneously breathing sevoflurane in oxygen, 3 drops of either povidone-iodine or BSS was instilled into each eye (right eye first). Respiratory rate was determined by measuring the peak-to-peak interval on the capnograph. This is similar to calculating heart rate by measuring the R-R interval on an ECG. HR, BP, SaO2, EtCO2, and expired sevoflurane were measured in each patient. Medical history information collected included history of prior surgeries, co-existing diseases, or apnea. Appropriate statistical analyses were performed for comparisons between the groups with respect to respiratory rate, HR, BP, expired sevoflurane, and co-existing diseases.

Group A - povidone-iodine ophthalmic solution, or Group B - ophthalmic balanced salt solution. This randomization will be determined using a simple randomization scheme provided by the study's statistician

Group A will receive three drops of povidone-iodine ophthalmic solution in each eye, with the right eye to receive the drops first.

Group B will receive three drops in each eye of ophthalmic balanced salt solution, with the right eye to receive the drops first.

Group A will receive three drops of povidone-iodine ophthalmic solution in each eye, with the right eye to receive the drops first. The eye drops will be administered by the study anesthesiologist. After application of either solution to the eyes of the patient, any change in ventilation can be detected and timed by observation of the capnography (end-tidal carbon dioxide) and direct observation of the chest wall with use of the iPhone stopwatch feature again. The capnograph is a standard monitor of respiration used during the administration of general anesthesia. Data collected at this time will include whether or not there was a change in respiration, what this change in respiration was, if assisted ventilation was required, how long assisted ventilation was required (if applicable), HR, BP, RR, SaO2 , ETCO2, InspSevo, and ExpSevo. This study intervention and data collection will take less than 5 minutes.

Group B will receive three drops in each eye of ophthalmic balanced salt solution. The eye drops will be administered by the study anesthesiologist. After application of either solution to the eyes of the patient, any change in ventilation can be detected and timed by observation of the capnography (end-tidal carbon dioxide) and direct observation of the chest wall with use of the iPhone stopwatch feature again. The capnograph is a standard monitor of respiration used during the administration of general anesthesia. Data collected at this time will include whether or not there was a change in respiration, what this change in respiration was, if assisted ventilation was required, how long assisted ventilation was required (if applicable), HR, BP, RR, SaO2 , ETCO2, InspSevo, and ExpSevo. This study intervention and data collection will take less than 5 minutes

The iPhone stopwatch application will be used and its 'lap button' feature to collect the respiration peak intervals (in seconds) for 5 breaths. Specifically, at the patient's peak inspiration (as seen on the capnography), the study member will start the stopwatch and proceed to hit the 'lap' button for the next 5 consecutive inspiration peaks. These data intervals will be recorded on the data sheet after the 5 breaths are over, as the intervals are conveniently stored and numbered below the stopwatch in the app

Inclusion Criteria Children between the ages of 1 year and 17 years Scheduled for strabismus surgery Anesthesia plan includes inhalational induction with sevoflurane and the use of a laryngeal mask airway (LMA) with spontaneous ventilation, per the attending anesthesiologist. Exclusion Criteria History of an adverse reaction to iodine History of any thyroid disease Patients who require tracheal intubation, as determined by the attending anesthesiologist; e.g. craniofacial anomalies. Patients with a contraindication to sevoflurane, such as malignant hyperthermia or severe left ventricular dysfunction. Inability or unwillingness of the subject or legal guardian/ representative to give informed consent.