Br. J. Anaesth. (1975), 47, 615
ACID PULMONARY ASPIRATION SYNDROME AFTER ANTACIDS A Case Report G. TAYLOR SUMMARY
At 08.00 hr, more senior anaesthetic assistance became available and an endotracheal tube was passed. Controlled ventilation with nitrous oxide and oxygen was continued with increments of suxamethonium. High gas flows were used and a carbon dioxide absorber was deliberately left out of the circuit. At the time of endotracheal intubation, a gastric sample was taken and the pH of the aspirate was found to be 3.5. The forceps delivery of a live infant with an Apgar score of 7 at 1 min and 9 at 5 min was completed uneventfully. At CASE REPORT A 33-year-old Caucasian female was admitted to the end of the operation (09.00 hr), the patient the labour ward on May 22, 1969, with ruptured was«found to be breathing satisfactorily; there were membranes and in early labour. At 02.00 hr, on a few crepitations at both lung bases. The endoMay 23, pethidine 150 mg and phenergan 50 mg tracheal tube was removed. At 10.45 hr, the patient was slightly cyanosed. were given i.m. to reduce pain. At 07.00 hr forceps Auscultation revealed fine crepitations all over the delivery was contemplated after the cervix had been fully dilated for about 60 min. During labour the chest, predominantly at the bases, but there was patient had received magnesium trisilicate (BPC) no evidence of bronchospasm. A chest x-ray 15 ml orally at 02.00 hr and 07.30 hr. Induction of showed pulmonary oedema consistent with the general anaesthesia with pre-oxygenation was com- features of the acid pulmonary aspiration syndrome. menced with the patient in a 15° head-down tilt. A needle was inserted into the brachial artery At 07.50 hr, methohexitone and suxamethonium and serial oxygen tension and pH measurewere given i.v. Endotracheal intubation was attemp- ments were made (table I). Following withdrawal ted but not accomplished at this stage and cricoid of the first arterial sample, hydrocortisone 300 mg compression was not used. The patient regurgitated was given i.v. and another 100 mg ijn. Oxygen was about 1,000 ml of gastric contents, some of which administered through a Poh/mask with an 8-litre was aspirated into the lungs. A 30° head-down flow, and antibiotic therapy was commenced. At no tilt was then instituted and pharyngeal suction was time did the patient have arterial hypotension or performed. The patient began to breathe spontan- a pulse rate greater than 100 beats/min. At 16.00 hr, the pulmonary signs were much eously and maintenance anaesthesia with nitrous oxide, oxygen and trichloroethylene was com- reduced, but considerable hypoxaemia was present when the patient was breathing air. The following menced using a face mask. day the oxygen tension values showed some G. TAYLOR, M.B., B.S., F.F.AJI.C.S.. Department of Anesimprovement. The condition of the patient conthetics, Stanford University School of Medicine, Stantinued to improve, although it was necessary ford, California 94305, U.SJL
Pulmonary aspiration of gastric contents is, fortunately, a relatively rare complication during anaesthesia for obstetric surgery. However, this complication can result in death of the patient should acid pulmonary aspiration (Mendelson's syndrome) develop (Mendelson, 1946; Arthure et al., 1972). Prompt recognition and aggressive treatment of the syndrome is the key to the successful recovery of these patients.
Downloaded from http://bja.oxfordjournals.org/ at Fudan University on May 10, 2015
This is a report of a patient who developed acid pulmonary aspiration syndrome following pulmonary aspiration of gastric contents at a pH of 3.5. The volume of the stomach contents was large and 15 ml of magnesium trisilicate was insufficient to prevent the effects of acid aspiration. After operation, considerable pulmonary shunting was demonstrable for several days. The patient was discharged home well, and a chest x-ray 2 months later showed no abnormality.
616
BRITISH JOURNAL OF ANAESTHESIA TABLE I. Blood-gas values after operation.
single-dose regime is not suitable for those patients in whom there is a large volume of gastric conPaoi gas Date (mm Hg) (units) tents. This patient had two doses of magnesium trisilicate. The normal routine in the author's air 7.40 May 23 33 66 7.40 mask O, hospital calls for the administration of 3-hourly air 27 7.41 doses when a patient is in established labour. A 83 7.40 mask O, dose at 05.00 hr on May 23 would have increased air 38 7.42 85 7.42 mask O, the pH of the gastric contents still further, possibly 35 air 7.41 May 24 preventing the development of acid pulmonary 140 7.42 mask O, aspiration syndrome. 33 air 7.43 May 26 83 7.41 mask O, This case report demonstrates that acid pulmon81 air 7.40 May 30 ary aspiration syndrome can develop with gastric 179 7.42 mask O, contents at a higher pH than was thought originally (Teabeaut, 1952; Vandam, 1965). The pH of the to continue intermittent oxygen therapy for 6 days. gastric contents in this patient was 3.5, and an Hydrocortisone therapy was stopped after 8 days. antacid prophylactic regime should be designed to A chest x-ray 2 months later showed normal pul- maintain gastric pH well above that value before the induction of anaesthesia. monary features. Table I illustrates the magnitude of abnormal REFERENCES arterial oxygen tension values in this patient after operation. Oxygen from a face mask was needed Adams, A. P.. Morgan, M., Jones, B. C., and McCormick, P. W. (1969). A case of massive aspiration of to alleviate hypoxaemia. Positive pressure ventilagastric contents during obstetric anaesthesia. Br. J. tion was not employed as the patient would have Anaesth., 41, 176. been intolerant of the procedure. However, the Arthure, H., Tomkinson, J., Organe, G., Bates, M., Adelstein, A. M., and Weatherall, J. A. C (1972). Report clinical signs of pulmonary oedema improved on confidential enquiries into maternal deaths in Engquickly, although it is clear that the stigmata of land and Wales: 1967-1969. HMSO Report No. 1. considerable shunting through the pulmonary Crawford, J. S. (1971). Anaesthesia for obstetric emergencies. Br. J. Anaesth., 43, 864. vasculature remained for many days. Time (hr) 11.25 11.55 14.10 15.30 18.15 19.45 11.00 11.30 09.30 10.00 11.35 12.05
Inspired
pH
During induction of anaesthesia in this patient, a 15° head-down tilt was employed without the use of cricoid compression. In addition, the patient had a large volume of gastric contents which was not apparent until regurgitation had occurred. The anaesthetic techniques used and the large volume of gastric contents regurgitated show some similarities to a previous report by Adams et al. (1969). Crawford (1971) has indicated that the use of cricoid pressure in association with a barbituratesuxamethonium sequence for emergency obstetric surgery would help control regurgitation of gastric contents in many patients. Gastric juice frequently has a pH of less than 2.5 in both pregnant and non-pregnant patients (Taylor and Pryse-Davies, 1966). However, it is rare to find a gastric pH of less than 1.2 (Taylor, 1966, unpublished data). Williams and Crawford (1971) indicated that a single 15-ml dose of magnesium trisilicate will buffer about 250 ml of gastric contents at a pH of 1.0, so that the resulting pH will be above 4.0. It follows, therefore, that a
Mendelson, C. L. (1946). Tht aspiration of stomach contents into the lungs during obstetric anesthesia. Am. J. Obstet. Gynecol, 52, 191. Taylor, G., and Pryse-Davies, J. (1966). The prophylactic use of antacids in the prevention of the acidpulmonary-aspiration syndrome (Mendelson's syndrome). Lancet, 1, 288. Teabeaut, J. R. (1952). Aspiration of gastric contents: an experimental study. Am. J. Pathol., 28, 51. Vandam, L. D. (1965). Aspiration of gastric contents in the operative period. N. Engl. J. Med., 273, 1206. Williams, M., and Crawford, J. S. (1971). Titration of magnesium trisilicate mixture against gastric acid secretion. Br. J. Anaesth., 43, 783. SYNDROME D'ASPIRATION PULMONAIRE ACIDE APRES INGESTION D'ANTIACIDES RESUME
Le present rapport porte sur un patient, chez lequel s'est manifest^ un syndrome d'aspiration pulmonaire acide a la suite de l'aspiration pulmonaire du contenu gastrique a un pH de 3,5. Le volume du contenu stomacal itait important et 15 ml de trisilicate de magnesium n'ont pas sum k empficher les effets de 1'aspiration acide. A la suite de l'intervention chirurgicale, des Changes pulmonaires considerables se sont manifestos pendant plusieurs jours. Le patient est rentrd chez lui en bonne santi et unri radiographie des poumons deux mois phis tard a donnf des risultats normaux.
Downloaded from http://bja.oxfordjournals.org/ at Fudan University on May 10, 2015
DISCUSSION
617
ACID PULMONARY ASPIRATION SYNDROME SAURE-LUNGENASPIRATIONSSYNDROM NACH ANTISAUREMITTELN
SINDROME POR ASPIRACION PULMONAR DE ACIDOS DESPUES DE ANTIACIDOS
ZUSAMMENFASSUNG
SUMARIO
Dies ist ein Bericht iiber einen Patienten, der ein SfiureLungenaspirationssyndrom entwickelte nach der Lungenaspiration gastrischer Inhalte bei 3,5 pH. Das Volumen des Mageninhalts war grofl, und 15 ml Magnesiumtrisilikat reichten nicht aus, urn die Wirkungen der Saureaspiration zu verhindern. Nach der Operation wurde mehrere Tage lang eine beachtliche Lungenumleitung demonstriert. Der Patient wurde gesund nach Hause entlassen, und eine Brust-Rontgenaufnahme zwei Monate spater zeigte eineD normalen Befund.
Este es el informe de un paciente que desarroll6 stodrome por aspiracidn pulmonsr de acidos que sigui6 e la aspiraci6n pulmonar de contenidos gastricos con un pH de 3,5. El volumen de los contenidos estomacales era grande y 15 ml de trisilicato de magnesio fue insufidente para impedir los efcctos de la aspiraci6n acida. Despues de la operaci6n, se observ6 un considerable cambio pulmonar durante varios dias. El paciente tui llevado a su casa sin problemas y un reconocimiento pectoral por rayos X, 2 meses mas tarde, indic
ACID PULMONARY ASPIRATION SYNDROME AFTER ANTACIDS A Case Report G. TAYLOR SUMMARY
At 08.00 hr, more senior anaesthetic assistance became available and an endotracheal tube was passed. Controlled ventilation with nitrous oxide and oxygen was continued with increments of suxamethonium. High gas flows were used and a carbon dioxide absorber was deliberately left out of the circuit. At the time of endotracheal intubation, a gastric sample was taken and the pH of the aspirate was found to be 3.5. The forceps delivery of a live infant with an Apgar score of 7 at 1 min and 9 at 5 min was completed uneventfully. At CASE REPORT A 33-year-old Caucasian female was admitted to the end of the operation (09.00 hr), the patient the labour ward on May 22, 1969, with ruptured was«found to be breathing satisfactorily; there were membranes and in early labour. At 02.00 hr, on a few crepitations at both lung bases. The endoMay 23, pethidine 150 mg and phenergan 50 mg tracheal tube was removed. At 10.45 hr, the patient was slightly cyanosed. were given i.m. to reduce pain. At 07.00 hr forceps Auscultation revealed fine crepitations all over the delivery was contemplated after the cervix had been fully dilated for about 60 min. During labour the chest, predominantly at the bases, but there was patient had received magnesium trisilicate (BPC) no evidence of bronchospasm. A chest x-ray 15 ml orally at 02.00 hr and 07.30 hr. Induction of showed pulmonary oedema consistent with the general anaesthesia with pre-oxygenation was com- features of the acid pulmonary aspiration syndrome. menced with the patient in a 15° head-down tilt. A needle was inserted into the brachial artery At 07.50 hr, methohexitone and suxamethonium and serial oxygen tension and pH measurewere given i.v. Endotracheal intubation was attemp- ments were made (table I). Following withdrawal ted but not accomplished at this stage and cricoid of the first arterial sample, hydrocortisone 300 mg compression was not used. The patient regurgitated was given i.v. and another 100 mg ijn. Oxygen was about 1,000 ml of gastric contents, some of which administered through a Poh/mask with an 8-litre was aspirated into the lungs. A 30° head-down flow, and antibiotic therapy was commenced. At no tilt was then instituted and pharyngeal suction was time did the patient have arterial hypotension or performed. The patient began to breathe spontan- a pulse rate greater than 100 beats/min. At 16.00 hr, the pulmonary signs were much eously and maintenance anaesthesia with nitrous oxide, oxygen and trichloroethylene was com- reduced, but considerable hypoxaemia was present when the patient was breathing air. The following menced using a face mask. day the oxygen tension values showed some G. TAYLOR, M.B., B.S., F.F.AJI.C.S.. Department of Anesimprovement. The condition of the patient conthetics, Stanford University School of Medicine, Stantinued to improve, although it was necessary ford, California 94305, U.SJL
Pulmonary aspiration of gastric contents is, fortunately, a relatively rare complication during anaesthesia for obstetric surgery. However, this complication can result in death of the patient should acid pulmonary aspiration (Mendelson's syndrome) develop (Mendelson, 1946; Arthure et al., 1972). Prompt recognition and aggressive treatment of the syndrome is the key to the successful recovery of these patients.
Downloaded from http://bja.oxfordjournals.org/ at Fudan University on May 10, 2015
This is a report of a patient who developed acid pulmonary aspiration syndrome following pulmonary aspiration of gastric contents at a pH of 3.5. The volume of the stomach contents was large and 15 ml of magnesium trisilicate was insufficient to prevent the effects of acid aspiration. After operation, considerable pulmonary shunting was demonstrable for several days. The patient was discharged home well, and a chest x-ray 2 months later showed no abnormality.
616
BRITISH JOURNAL OF ANAESTHESIA TABLE I. Blood-gas values after operation.
single-dose regime is not suitable for those patients in whom there is a large volume of gastric conPaoi gas Date (mm Hg) (units) tents. This patient had two doses of magnesium trisilicate. The normal routine in the author's air 7.40 May 23 33 66 7.40 mask O, hospital calls for the administration of 3-hourly air 27 7.41 doses when a patient is in established labour. A 83 7.40 mask O, dose at 05.00 hr on May 23 would have increased air 38 7.42 85 7.42 mask O, the pH of the gastric contents still further, possibly 35 air 7.41 May 24 preventing the development of acid pulmonary 140 7.42 mask O, aspiration syndrome. 33 air 7.43 May 26 83 7.41 mask O, This case report demonstrates that acid pulmon81 air 7.40 May 30 ary aspiration syndrome can develop with gastric 179 7.42 mask O, contents at a higher pH than was thought originally (Teabeaut, 1952; Vandam, 1965). The pH of the to continue intermittent oxygen therapy for 6 days. gastric contents in this patient was 3.5, and an Hydrocortisone therapy was stopped after 8 days. antacid prophylactic regime should be designed to A chest x-ray 2 months later showed normal pul- maintain gastric pH well above that value before the induction of anaesthesia. monary features. Table I illustrates the magnitude of abnormal REFERENCES arterial oxygen tension values in this patient after operation. Oxygen from a face mask was needed Adams, A. P.. Morgan, M., Jones, B. C., and McCormick, P. W. (1969). A case of massive aspiration of to alleviate hypoxaemia. Positive pressure ventilagastric contents during obstetric anaesthesia. Br. J. tion was not employed as the patient would have Anaesth., 41, 176. been intolerant of the procedure. However, the Arthure, H., Tomkinson, J., Organe, G., Bates, M., Adelstein, A. M., and Weatherall, J. A. C (1972). Report clinical signs of pulmonary oedema improved on confidential enquiries into maternal deaths in Engquickly, although it is clear that the stigmata of land and Wales: 1967-1969. HMSO Report No. 1. considerable shunting through the pulmonary Crawford, J. S. (1971). Anaesthesia for obstetric emergencies. Br. J. Anaesth., 43, 864. vasculature remained for many days. Time (hr) 11.25 11.55 14.10 15.30 18.15 19.45 11.00 11.30 09.30 10.00 11.35 12.05
Inspired
pH
During induction of anaesthesia in this patient, a 15° head-down tilt was employed without the use of cricoid compression. In addition, the patient had a large volume of gastric contents which was not apparent until regurgitation had occurred. The anaesthetic techniques used and the large volume of gastric contents regurgitated show some similarities to a previous report by Adams et al. (1969). Crawford (1971) has indicated that the use of cricoid pressure in association with a barbituratesuxamethonium sequence for emergency obstetric surgery would help control regurgitation of gastric contents in many patients. Gastric juice frequently has a pH of less than 2.5 in both pregnant and non-pregnant patients (Taylor and Pryse-Davies, 1966). However, it is rare to find a gastric pH of less than 1.2 (Taylor, 1966, unpublished data). Williams and Crawford (1971) indicated that a single 15-ml dose of magnesium trisilicate will buffer about 250 ml of gastric contents at a pH of 1.0, so that the resulting pH will be above 4.0. It follows, therefore, that a
Mendelson, C. L. (1946). Tht aspiration of stomach contents into the lungs during obstetric anesthesia. Am. J. Obstet. Gynecol, 52, 191. Taylor, G., and Pryse-Davies, J. (1966). The prophylactic use of antacids in the prevention of the acidpulmonary-aspiration syndrome (Mendelson's syndrome). Lancet, 1, 288. Teabeaut, J. R. (1952). Aspiration of gastric contents: an experimental study. Am. J. Pathol., 28, 51. Vandam, L. D. (1965). Aspiration of gastric contents in the operative period. N. Engl. J. Med., 273, 1206. Williams, M., and Crawford, J. S. (1971). Titration of magnesium trisilicate mixture against gastric acid secretion. Br. J. Anaesth., 43, 783. SYNDROME D'ASPIRATION PULMONAIRE ACIDE APRES INGESTION D'ANTIACIDES RESUME
Le present rapport porte sur un patient, chez lequel s'est manifest^ un syndrome d'aspiration pulmonaire acide a la suite de l'aspiration pulmonaire du contenu gastrique a un pH de 3,5. Le volume du contenu stomacal itait important et 15 ml de trisilicate de magnesium n'ont pas sum k empficher les effets de 1'aspiration acide. A la suite de l'intervention chirurgicale, des Changes pulmonaires considerables se sont manifestos pendant plusieurs jours. Le patient est rentrd chez lui en bonne santi et unri radiographie des poumons deux mois phis tard a donnf des risultats normaux.
Downloaded from http://bja.oxfordjournals.org/ at Fudan University on May 10, 2015
DISCUSSION
617
ACID PULMONARY ASPIRATION SYNDROME SAURE-LUNGENASPIRATIONSSYNDROM NACH ANTISAUREMITTELN
SINDROME POR ASPIRACION PULMONAR DE ACIDOS DESPUES DE ANTIACIDOS
ZUSAMMENFASSUNG
SUMARIO
Dies ist ein Bericht iiber einen Patienten, der ein SfiureLungenaspirationssyndrom entwickelte nach der Lungenaspiration gastrischer Inhalte bei 3,5 pH. Das Volumen des Mageninhalts war grofl, und 15 ml Magnesiumtrisilikat reichten nicht aus, urn die Wirkungen der Saureaspiration zu verhindern. Nach der Operation wurde mehrere Tage lang eine beachtliche Lungenumleitung demonstriert. Der Patient wurde gesund nach Hause entlassen, und eine Brust-Rontgenaufnahme zwei Monate spater zeigte eineD normalen Befund.
Este es el informe de un paciente que desarroll6 stodrome por aspiracidn pulmonsr de acidos que sigui6 e la aspiraci6n pulmonar de contenidos gastricos con un pH de 3,5. El volumen de los contenidos estomacales era grande y 15 ml de trisilicato de magnesio fue insufidente para impedir los efcctos de la aspiraci6n acida. Despues de la operaci6n, se observ6 un considerable cambio pulmonar durante varios dias. El paciente tui llevado a su casa sin problemas y un reconocimiento pectoral por rayos X, 2 meses mas tarde, indic
