Does pressure support ventilation improve the postoperative outcome of adeno-tonsillectomy patients? A prospective randomized trial

BackgroundSpontaneous ventilation (SV) is used for adeno/tonsillectomy in children. However, inhalational anesthetics produce dose dependent decrease in minute ventilation. We tested the impact of PSV on awakening time, and length of PACU stay.Methods34 patients were randomized into two groups; PS ventilation group and SV group. Premedication and induction were similar in both groups. Patients in PS group were ventilated with Pinsp set to deliver 8 ml/kg VT, keeping ETCO2 between 35 and 45 mmHg. Any episodes of hypoventilation were recorded and corrected by manual support of ventilation.Upon completion of surgery, time-to-extubate was recorded. Length of PACU stay, agitation and CHEOPS scores, PONV and desaturation episodes were also recorded. Results are presented as mean (SD), median (interquartile range), or number of patients as appropriate. A P value < 0.05 was considered significant.ResultsExtubation time (min) [mean (SD)] was longer in SV group than PS group [7.8 (2.1) vs. 5.5(1.4), P < 0.001]. In the SV group 9 patients had episodes of hypoventilation that necessitated manual assist of ventilation. Pain scores were higher in SV group than PS group. Duration of stay in PACU [mean (SD)] in minutes was longer in SV group than PS group [44.3(7.4) vs. 39.4(5.7), P = 0.02]. All but one patient in the PS group needed postoperative rescue meperidine analgesia. The mean (SD) time needed for rescue meperidine analgesia was 27.1(8.9) in PS group and 21.8(9.4) in SV group (P = 0.04).ConclusionPSV carries the advantages of overcoming the effects of narcotics and inhaled anesthetics on spontaneously ventilated adeno-tonsillectomy patients. They suffer less pain and spend less time in the PACU.