2 | CASE HISTORY
A 20-year-old man (height: 156 cm; weight: 58 kg) was admitted to our institution for SSRO surgery under general anesthesia due to mandibular protrusion. He had a history of SWS and had swelling of the upper lip and maxillary gingiva due to angiomas, bilateral facial PWS, and right hemiparesis (Figure 1). When we saw his face, we realized that mask ventilation might be difficult because his upper lip was markedly swollen and protruded due to angiomas. Therefore, we checked the fitting of a large face mask (Air Cushion Face Mask, Large size for adults: KOOMEDICALJAPAN, Tokyo, Japan) and total-face mask (PerformaxSE, XL size: Philips Respironics, Tokyo, Japan) for mask ventilation at induction.
In the preoperative evaluation, the patient’s blood pressure, pulse rate, and peripheral arterial oxygen saturation (SpO2) were 121/69 mmHg, 69 bpm, and 97%, respectively. Laboratory tests and chest radiography showed no abnormalities. Electrocardiogram showed sinus rhythm. The brain magnetic resonance imaging scan showed angiomatosis along the cerebral gyrus and brain atrophy. The neurosurgeon instructed us to carefully control blood pressure during the perioperative period because the rupture of angiomas may lead to life-threatening hemorrhage.
We consulted an otolaryngologist to evaluate the nasal cavity and larynx before surgery because airway management in SSRO surgery should be performed by nasal intubation to check the bite during surgery. Computed tomography scans revealed nasal septal curvature and remarkable bony thickening of the inferior nasal dorsum on either side (Figure 2). Fiberscope examination revealed angiomatosis in front of the inferior nasal dorsum. No problems were observed around the larynx. The otolaryngologist suggested that nasal intubation was very severe in this case. Thus, we planned to perform airway management during surgery by submental intubation (SMI), not nasal intubation.
We also consulted a urologist to evaluate the ureter and bladder using cystoscopy to avoid the rupture of angiomas by urinary drainage. Examination revealed no angiomas or stenoses in the ureter or bladder.
This patient had a history of glaucoma and retinal detachment, for which he underwent ophthalmic surgery under general anesthesia at the ages of 10, 12, and 16 years, and he had been on acetazolamide (250 mg/day). Furthermore, he had a history of epilepsy. However, seizures had not occurred for more than 10 years without medication. His intellectual ability was borderline, and he showed no problems in verbal communication.
No premedication was provided. Noninvasive blood pressure, electrocardiogram results (lead II), oxygen saturation, and muscle relaxation were monitored during general anesthesia. Furthermore, the depth of anesthesia was monitored using an entropy monitor (GE Healthcare, Chicago, IL, USA). The baseline blood pressure, heart rate, and SpO2 were 123/66 mmHg, 92 bpm, and 99%, respectively, before induction. Oxygen was delivered via a face mask at a flow rate of 6 L/min, and Ringer’s acetate solution was infused. Rapid induction was performed with propofol (target concentration 4 μg/ml) and remifentanil (30 μg and 0.35 μg/kg/min). Mask ventilation was possible when a face mask (large size) with an oral airway was used, but a little pressure was required on the upper lip (Figure 3A). Therefore, we changed to a full-face mask (extra-large size) to avoid pressure on the upper lip. The full-face mask allowed us to perform mask ventilation without any pressure on the upper lip (Figure 3B). After we confirmed that we could perform mask ventilation, rocuronium (30 mg) was administered. Oral intubation was performed using a video laryngoscope (McGRATH™ MAC, Aircraft Medical, Edinburgh, UK), and we visually confirmed that there was no angioma in the oro- and laryngopharynx at that time. A wire-reinforced tube (7.0 mm I.D.) was placed into the trachea. After that, general anesthesia was maintained with propofol (target concentration 2.5–2.8 μg/ml) and remifentanil (0.13–0.3 μg/kg/min).
The SMI method was initiated. The surgeon made an incision in the submental skin, and a Kelly forceps was bluntly introduced through the submental incision to the floor of the mouth. Then, the Kelly forceps was replaced with 2.5, 5, and 10 ml syringes to enlarge the tunnel. Ventilation with 100% oxygen was performed to avoid apnea in the following procedures. The endotracheal tube (ETT) was removed from the ventilatory circuit. A sterilized echo probe cover was then placed over the ETT and held with a rubber band at the base of the pilot balloon (Figure 4). A Kelly forceps was inserted from the floor of the mouth to grasp the echo probe cover. The echo probe cover placed on the pilot balloon was pulled through the enlarged tunnel of the floor of the mouth using a Kelly forceps, and the ETT was allowed to pass through the tunnel. The ETT was reconnected to the ventilatory circuit. Apnea duration was 60 s, and no decreased SpO2 was observed. We confirmed with bronchial fibers that the tip of the ETT was properly positioned even when the mouth was opened and closed, and the tube was secured to the skin with a 2-0 silk suture (Figure 5A).
After the completion of the SMI, the scheduled SSRO surgery was performed. The tube did not interfere with the operation during surgery, and no accidental extubation occurred. The patient’s blood pressure, pulse rate, SpO2, and EtCO2 were 90–120/40–70 mmHg, 70–90 bpm, 98%–100%, and 35–45 cm H2O, respectively, and no complications were not observed during surgery.
Immediately after the surgery, ventilation with 100% oxygen was performed to transfer the SMI from submental to oral intubation. In this process, the ETT’s connector was stuck in the tunnel because of its wings (Figure 5B). Therefore, the transition took a little bit longer than usual. The apnea duration was 90 s. However, no decreased SpO2 was observed. After that, the tunnel was closed with sutures.
The anesthetics were stopped after visual confirmation of hemostasis in the oral cavity. The patient was extubated after confirmation of the recovery of spontaneous respiration, body movement, spontaneous eye-opening, and deglutition reflex. After extubation, the patient was transferred to the ward with stable vital signs. The surgical time, anesthetic time, and bleeding volume were 191 min, 254 min, and 36 ml, respectively. The patient was discharged from the hospital on postoperative day 11 without any complications.