RESUMO
Introduction: Priming refers to administration of asubanaesthetic dose (priming dose) of an agent prior to itsactual anaesthetic dose. The “priming principle” is a methodto reduce the total dose requirements of a drug. This studywas undertaken to study the effect of priming principle oninduction dose requirements of propofol.Material and Methods: Sixty (60) patients with AmericanSociety of Anaesthesiologists (ASA) I and ASA II grades,of both sexes, aged 18-55 years, and undergoing electivesurgical procedures under general anaesthesia were randomlyallocated into two equal groups with 30 patients each. GroupI (control) received calculated induction dose of injection(inj.) propofol 2mg/kg. Group II (study) received 20% of totalcalculated induction dose of propofol 2 mg/kg as a primingdose and remaining dose after 60 seconds titrated till loss ofthe eyelash reflex.Results: The control group consumed a higher dose of inj.propofol (2 mg/kg) as compared with the study group (1.34± 0.28 mg/kg), i.e., there was 33% reduction of the total dosein the study group. The hemodynamic changes in HR, SBP,DBP, MAP and RPP at 30 minutes before induction, justbefore induction, immediately after intubation and 5 minutesafter induction were similar in both groups (P > 0.05) .Thehemodynamic changes in HR, SBP, DBP, MAP and RPP atone minute after induction were statistically significant inboth the groups (P< 0.05). Incidence of pain and apnea wascomparable in both groups but hypotension was seen in 4patients in control group and none in study group.Conclusion: The priming technique effectively reduced thetotal induction dose requirements of propofol and favourablyreduced extent of hypotension following induction withpropofol.
RESUMO
Abstract Background and objectives The purpose of this study was to compare the endotracheal tube cuff pressure changes during laparoscopic surgeries using air versus nitrous-oxide in anesthetic gas mixture; and to observe the incidences of postoperative sore throat, hoarseness and dysphagia. Methods Total 100 patients scheduled for elective laparoscopic abdominal surgery were allocated into two groups. Group A (n = 50) received air while Group N (n = 50) received nitrous-oxide in anesthetic gas mixture. After endotracheal intubation, cuff was inflated with air to achieve sealing pressure. Cuff pressure at baseline (sealing pressure), 30 min, 60 min and 90 min was recorded with a manometer. Incidence of sore throat, hoarseness and dysphagia was noted at the time of discharge from post-anesthesia care unit and 24 h after extubation. Results Cuff pressure increased from baseline in both the groups. The increase in cuff pressure in Group N was greater than that in Group A at all time points studied (p < 0.001). Within Group A, cuff pressure increased more at 90 min than at 30 min (p < 0.05). Within Group N, increase in cuff pressure was more at each time point (30, 60 and 90 min) than its previous time point (p < 0.05). The incidence of sore throat in post-anesthesia care unit was higher in Group N than in Group A. Conclusion Use of nitrous-oxide during laparoscopy increases cuff pressure resulting in increased incidence of postoperative sore throat. Cuff pressure should be monitored routinely during laparoscopy with nitrous-oxide anesthesia.
Resumo Justificativa e objetivos O objetivo deste estudo foi comparar as alterações na pressão do balonete do tubo endotraqueal durante cirurgias laparoscópicas usando ar versus óxido nitroso na mistura dos gases anestésicos e observar a incidência de dor de garganta, rouquidão e disfagia no pós-operatório. Métodos No total, 100 pacientes agendados para cirurgia abdominal laparoscópica eletiva foram alocados em dois grupos: Grupo A (n = 50) recebeu ar e Grupo N (n = 50) recebeu óxido nitroso na mistura de gases anestésicos. Após a intubação endotraqueal, o balonete foi insuflado com ar para obter a pressão de vedação. As pressões do balonete na fase basal (pressão de vedação), aos 30 min, 60 min e 90 min foram registradas com um manômetro. A incidência de dor de garganta, rouquidão e disfagia foi observada no momento da alta da sala de recuperação pós-anestésica e 24 horas após a extubacão. Resultados A pressão do balonete aumentou em ambos os grupos, comparada à pressão basal. O aumento da pressão do balonete foi maior no Grupo N do que no Grupo A em todos os tempos avaliados (p < 0,001). No Grupo A, o aumento da pressão do balonete foi maior aos 90 min do que aos 30 min (p < 0,05). No Grupo N, o aumento da pressão do balonete foi maior em cada um dos tempos (30, 60 e 90 min) do que no tempo anteriormente mensurado (p < 0,05). A incidência de dor de garganta na sala de recuperação pós-anestésica foi maior no Grupo N do que no Grupo A. Conclusão O uso de óxido nitroso durante a laparoscopia aumenta a pressão do balonete, resulta em aumento na incidência de dor da garganta no pós-operatório. A pressão do balonete deve ser rotineiramente monitorada durante a laparoscopia sob anestesia com óxido nitroso.