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Anestvice Inc. Phase II Clinical Trials for PC-LM Device have been successfully completed.

The research was conducted on 24 patients ranging in age from 13 to 74 years (the average age was 46.6 ±5.4), who underwent surgery in the urology clinic of the Rostov State Medical University. It was sponsored by Anestvice Inc. www.anestvice.com Baltimore based research and development company. All of the patients had an ASA score of 1 or 2. The patients were divided into two groups according to the type of anesthesia they received and the type of ventilation used during their operation. The first group consisted of 19 patients who underwent operations on the kidneys and upper urinary tracts -- a radical nephrectomy with tumors of the kidneys, a surgical intervention for the treatment of kidney stones and hydronephrosis. The operations were conducted under total intravenous anesthesia (propofol, fentanyl, pipecuronium) using CMV to ventilate the lungs. The length of the anesthesia was 2-3 hours. The second group consisted of 5 patients who underwent operations under spinal or combined spinal-epidural anesthesia in conjunction with intravenous propofol anesthesia. These patients received no artificial respiraton; during the operation they breathed naturally. The operations in this group were 2 penile implants and 3 radical cystectomies with intestinoplastiy of the bladder. In connection with its length of 7 - 8 hours, the operation on a cancerous bladder was of particular interest.

The LMA ProSeal laryngeal mask was used with all patients, and the pressure controller under study was attached to the cuff before inflation occured. The cuff was inflated until the pointer aligned with a mark on the pressure control device.
Measurement of the pressure in the cuff was carried out in at four stages: 1 – upon inflation, 2 – after the patient was turned over (group 1) or at the beginning of the operation (group 2), 3 - one hour after the initial incision and 4 - at the end of the operation.

Results. Sufficient ventilation of the lungs was achieved in all cases based on data from pulse oximetry, capnography and through selective monitoring of the gas content of blood during radical cystectomies. An observation of note was made in one case where the regurgitation of the contents of the stomach occured in connection with the surgical procedures. Aspiration did not occur in this case, which indicates the effectiveness with which the lungs are protected by a correctly applied LMA ProSeal mask.

Conclusions:

1. The use of a pressure controller to regulate air supply to the cuff of a laryngeal mask during nephrourologic operations allows for the constant supply of the optimal level of pressure both during artificial ventilation of the lungs and during natural breathing.

2. The use of a pressure controller increases the effectiveness of laryngeal masks and, consequently, patient safety improves. Pressure controllers, therefore, are recommended for wide use.