Brazilian Journal of Anesthesiology
https://bjan-sba.org/article/doi/10.1590/S0034-70942004000200009
Brazilian Journal of Anesthesiology
Scientific Article

Análise macroscópica infra-vermelha da difusão do óxido nitroso via inalatória para a cavidade abdominal, em ratos submetidos a pneumoperitônio

Macroscopic infrared analysis of inhaled nitrous oxide diffusion to abdominal cavity in rats submitted to pneumoperitoneum

Daniel Colman; Marcos Leal Brioschi; Mário Cimbalista Júnior; Elizabeth Mila Tambara; Maria Célia Barbosa Fabrício de Melo; Leonardo Pimpão Blume

http://dx.doi.org/10.1590/S0034-70942004000200009 Braz J Anesthesiol, vol.54, n2, p.218-228, 2004
PDF Português
PDF English
Downloads: 0
Views: 889

Resumo

JUSTIFICATIVA E OBJETIVOS: O óxido nitroso (N2O), por ser uma estrutura tri-atômica assimétrica, assume características de alta emissão e absorção de energia no espectro infra-vermelho, com um pico característico de absorção em 4,5 µm, o que o torna visível ao infra-vermelho curto, quando contrastado com uma fonte emissora de calor (anteparo quente). Diversos autores têm descrito a difusão do N2O para cavidades fechadas por métodos como cromatografia gasosa e analisador de gases, que não permitem um estudo macroscópico detalhado do gás. O presente estudo teve como objetivo a filmagem macroscópica no espectro infra-vermelho da difusão de N2O, utilizado em anestesia inalatória, para a cavidade peritoneal de ratos submetidos a pneumoperitônio de 20 mmHg com ar ambiente. MÉTODO: Dividiu-se os animais em três grupos, de acordo com o anestésico utilizado: I - controle venoso: tiopental intra-peritoneal; II - controle inalatório: isoflurano a 1,2% em O2 100%; III - óxido nitroso: N2O 66% em oxigênio e isoflurano a 0,6%. Os termogramas provenientes da descompressão abdominal foram obtidos, por meio de um radiômetro AGEMA 550 filmados a 7 quadros por segundo. RESULTADOS: O N2O demonstrou-se visível ao infra-vermelho. No momento da descompressão abdominal, não houve nos grupos I e II termogramas com rastros de gases visíveis ao infra-vermelho. Houve, porém, rastros de gases visíveis ao infra-vermelho no grupo III. CONCLUSÕES: Conclui-se que o óxido nitroso inalatório a 66% difundiu-se para a cavidade peritoneal de ratos submetidos a pneumoperitônio de 20 mmHg com ar ambiente, sem aumento de pressão intra-abdominal.

Palavras-chave

ANESTÉSICOS, ANESTÉSICOS, ANIMAL, TÉCNICAS DE MEDIÇÃO

Abstract

BACKGROUND AND OBJECTIVES: Nitrous oxide (N2O), for its tri-atomic asymmetric structure, has high energy emission and absorption characteristics within the infrared spectrum, with maximum absorption at 4.5 µm, what makes it visible at short infrared, when contrasted with a heat emission source (hot support). Many authors have described N2O diffusion to closed cavities by chromatography methods and gas analyzers, which do not allow a detailed macroscopic study of the gas. This study aimed at macroscopically filming in the infrared spectrum inhaled N2O diffusion to the peritoneal cavity of rats submitted to 20 mmHg room air pneumoperitoneum. METHODS: Animals where divided in three groups according to the anesthetic drug: I - Intravenous control: intraperitoneal thiopental; II - inhaled control: 1.2% isoflurane in 100% O2; III - nitrous oxide: 66% N2O in oxygen and 0.6% isoflurane. Thermal images of abdominal decompression where captured by an AGEMA 550 radiometer filmed at 7 frames per second. RESULTS: N2O was visible to infrared. At abdominal decompression, groups I and II have not shown visible gas traces at infrared thermographs, while group III had visible infrared traces. CONCLUSIONS: Our conclusion was that 66% inhaled nitrous oxide has diffused to peritoneal cavity of rats submitted to 20 mmHg room air pneumoperitoneum, with no intra-abdominal pressure increase.

Keywords

ANESTHETICS, ANESTHETICS, ANIMAL, MEASUREMENT TECHNIQUES

References

Nocite JR. Óxido nitroso: perspectivas para o ano 2000. Rev Bras Anestesiol. 1993;43:157-158.

Eger II EI, Larson Jr CP. Anaesthetic solubility in blood and tissues: values and significance. Br J Anaesth. 1964;36:140-144.

Saidman LJ, Eger II EI. Effect of nitrous oxide and of narcotic premedication on the alveolar concentration of halothane required for anesthesia. Anesthesiology. 1964;25:302-306.

Thornton JA, Fleming JS, Goldberg AD. Cardiovascular effects of 50% nitrous oxide and 50% oxygen mixture. Anaesthesia. 1973;28:484-489.

Moore PM, Maldague XPV. Infrared and Thermal Testing. 1988;3.

Whitcher C, Piziali R. Monitoring occupational exposure to inhalation anesthetics. Anesth Analg. 1977;56:778-785.

Carlsson P, Ljungqvist B, Neikter K. Thermocamera studies of gases and vapours. Br J Ind Med. 1982;39:300-305.

Allander C, Carlsson P, Hallen B et al. Thermocamera, a macroscopic method for the study of pollution with nitrous oxide in operating theaters. Acta Anaesthesiol Scand. 1981;25:21-24.

Saidman LJ, Eger EI. Change in cerebrospinal fluid pressure during pneumoencephalography under nitrous oxide anesthesia. Anesthesiology. 1965;26:67-72.

Patterson ME, Bartlett PC. Hearing impairment caused by intratympanic pressure changes during general anesthesia. Laryngoscope. 1976;86:399-404.

Man A, Segal S, Ezra S. Ear injury caused by elevated intratympanic pressure during general anesthesia. Acta Anaesthesiol Scand. 1980;24:224-226.

Katayama M, Panhoca R, Vieira JL et al. Alterações no ouvido médio induzidas pelo óxido nitroso e suas implicações clínicas. Rev Bras Anestesiol. 1992;42:397-404.

Katayama M, Vieira JL, Campos JL. Óxido nitroso: uma boa opção como gás para pneumoperitôneo nas colecistectomias por videolaparoscopia sob anestesia geral. Rev Bras Anestesiol. 1996;46:78-87.

Scheinin R, Lindgren L, Scheinin TM. Peroperative nitrous oxide delays bowel function after colonic surgery. Br J Anaesth. 1990;64:154-158.

Spivak H, Nudelman I, Fuco V. Laparoscopic extraperitoneal inguinal hernia repair with spinal anesthesia and nitrous oxide insuflation. Surg Endosc. 1999;13:1026-1029.

Gagge AP, Nishi Y. Heat Exchange between Human Skin Surface and Thermal Environment. Handbook of Physiology: Reactions to Environmental Agents. 1977:69-92.

Dripps RD. Evaluation of the Response to Anesthetics: the Signs and Stages. Introduction to Anaesthesia: The Principle of Safe Practice. 1977.

Cunningham AJ. Anesthetic implications of laparoscopic surgery. Yale J Biol Med. 1998;71:551-578.

Eleftheriadis E, Kotzampassi K, Papanotas K. Gut ischemia, oxidative stress and bacterial translocation in elevated abdominal pressure in rats. World J Surg. 1996;20:11-16.

Diemunsch PA, Torp KD, Van Dorsselaer T. Nitrous oxide fraction in the carbon dioxide pneumoperitoneum during laparoscopy under general inhaled anesthesia in pigs. Anesth Analg. 2000;90:951-953.

Diemunsch PA, Van Dorsselaer T, Torp KD. Calibrated pneumoperitoneal venting to prevent N2O accumulation in the CO2 pneumoperitoneum during laparoscopy with inhaled anesthesia: an experimental study in pigs. Anesth Analg. 2002;94:1014-1018.

Hunter JG, Staheli J, Oddsdottir M. Nitrous oxide pneumoperitoneum revisited: Is there a risk of combustion?. Surg Endosc. 1995;9:501-504.

Taylor E, Feinstein R, White PF. Anesthesia for laparoscopic cholecystectomy. Is nitrous oxide contraindicated? Anesthesiology. 1992;76:541-543.

Neuman GG, Sidebotham G, Negoianu E. Laparoscopy explosion hazards with nitrous oxide. Anesthesiology. 1993;78:875-879.

Corall IM, Elias JA, Strunin L. Laparoscopy explosion hazards with nitrous oxide. Br Med J. 1975;4:5991:288.

Katayama M, Campos JL, Cardoso PRO. Anestesia geral para colecistectomia laparoscópica: efeito do óxido nitroso sobre a ventilação pulmonar. Rev Bras Anestesiol. 1993;43:313-321.

Johannsen G, Andersen M, Juhl B. The effect of general anaesthesia on the hemodynamic events during laparoscopy with CO2 insuflation. Acta Anaesthesiol Scand. 1989;33:132-136.

Marschall RL, Jebson PJR, Davie IT. Circulatory effects of peritoneal insufflation with nitrous oxide. Br J Anaesth. 1982;44:1183-1187.

Ooka T, Kawano Y, Kosaka Y. Blood gas changes during laparoscopic cholecystectomy: comparative study of N2O pneumoperitoneum and CO2 pneumoperitoneum. Masui. 1993;42:398-401.

Minoli G, Terruzzi V, Spinzi GC. The influence of carbon dioxide and nitrous oxide on pain during laparoscopy: a double-blind controlled trial. Gastrointestinal Endoscopy. 1982;28:173-175.

5dd7f1d50e8825b70713f286 rba Articles
Links & Downloads
2352-2291 (Electronic) 0104-0014 (Printed)
Braz J Anesthesiol ©2024 All rights reserved.

Braz J Anesthesiol

Share this page
Page Sections