ABSTRACT
Objective To explore the effects of airway peak pressure (Ppeak)guidance on the minimum laryngeal mask airway (LMA)intracuff pressure (ICP)setting during general anesthesia. Methods Sixty patients,aged 18-65 years,ASA physical status Ⅰ or Ⅱ,scheduled for elective gy-necological laparoscopic operation under general anesthesia were enrolled.The patients were randomly divided into pressure-regulated group (group P)and control group (group C)with 30 cases in each group.Size 4 Supreme LMA was inserted in after general anesthesia induction.Air was injected into the cuff to make ICP achieve 60 cm H2O.Volume-controlled ventilation was selected and Ppeak was recorded.In group P,all the gas in the LMA cuff was sucked out,and then air was injected in during expiration phase to make ICP achieve the level of Ppeak.If air leakage occurred,ICP was increased by 5 cm H2O each time until no gas leaked from the oropharynx.After pneumoperitoneum,the cuff was inflated to make ICP achieve 60 cm H2O and Ppeak was recorded once more.Then all the gas in the LMA cuff was sucked out,and air was injected into the cuff to make ICP achieve the level of Ppeak as the above method till the end of operation.In group C,ICP was maintained at 60 cm H2O.Ppeak, ICP and the intracuff gas volume were recorded before and after pneumoperitoneum.ICP during in-spiratory phase in the two groups was measured.Tidal volume during inspiration(Vti)and expiration (Vte)in the two groups were recorded,and the air leakage fraction (LF)was calculated as [(Vti-Vte)/Vti×100%].Laryngopharyngeal complications of all the patients in 24 hours after surgeries were also recorded.Results The intracuff gas volume before and after pneumoperitoneum and ICP were decreased significantly in group P compared with group C (P<0.05).There was no difference in LF between the two groups.Compared with group C,there were fewer patients with postoperative throat pain and swallow discomfort in group P (P<0.05).Conclusion ICP at the level of Ppeak plus 0-5 cm H2O during LMA ventilation can provide better sealing effect and less laryngopharyngeal com-plications.
ABSTRACT
Objective To evaluate the efficacy of transverse thoracic muscle plane-thoracic nerve block combined with general anesthesia when used for modified radical mastectomy. Methods Sixty female patients, of American Society of Anesthesiologists physical statusⅠ or Ⅱ, aged 45-63 yr, weighing 48-72 kg, scheduled for elective modified radical mastectomy, were divided into 3 groups ( n=20 each) using a random number table method: thoracic nerve block-general anesthesia group ( group P+G ) , transverse thoracic muscle plane-thoracic nerve block-general anesthesia group ( group T+P+G) and general anesthesia group ( group G ) . Anesthesia was induced with midazolam, propofol, fentanyl and cisatracurium and maintained with sevoflurane, fentanyl and cisatracurium. Thoracic nerve block typeⅠ and Ⅱ was per-formed after implanting laryngeal mask airway in group P+G. Transverse thoracic muscle plane block was performed after performing thoracic nerve block typeⅠandⅡin group T+P+G. Flurbiprofen 50 mg was in-travenously injected after operation as a rescue analgesic to maintain the Visual Analogue Scale score≤3. The consumption of opioids, emergence time and time for removal of the laryngeal mask airway were recor-ded. Ramsay sedation score was recorded at 10 min after removal of the laryngeal mask airway. The require-ment for rescue analgesia, time of passing flatus and development of nausea and vomiting within 24 h after operation were recorded. Results Compared with group G, the emergence time, time for removal of the laryngeal mask airway and time of passing flatus were significantly shortened, and the Ramsay sedation score, consumption of fentanyl and requirement for rescue analgesia were decreased in P+G and T+P+G groups ( P<0. 05) , and the incidence of nausea and vomiting was significantly decreased in group T+P+G ( P<0. 05) . Compared with group P+G, the time for removal of the laryngeal mask airway and time of pass-ing flatus were significantly shortened, the consumption of fentanyl was decreased ( P<0. 05) , and no sig-nificant change was found in the requirement for rescue analgesia or incidence of nausea and vomiting in group T+P+G ( P>0. 05) . Conclusion Transverse thoracic muscle plane-thoracic nerve block combined with general anesthesia can provide satisfactory perioperative analgesia and is helpful in improving prognosis for the patients undergoing modified radical mastectomy.