70
Comment
of analysis. Of questionnaires that we have examined to date, all (100) have indicated that the anaesthetist routinely administers one or more anaesthetic agents during CPB. Undoubtedly, there are occasions during cardiac anaesthesia when lifethreatening cardiovascular collapse may occur and it can be argued that the level of anaesthesia should be lightened to eliminate any possible adverse effects that the anaesthetic agents may have on the cardiovascular system. These occasions can occur before, and more frequently after, CPB. This is not the case during CPB when the circulation is mechanically supported. Thus, there can be no reason why some form of anaesthesia should not be administered, whether intravenous, opioid or volatile anaesthetic agent, during CPB. Hypothermia, without doubt, produces unconsciousness, but rewarming commences long before the end of CPB and is associated with immediate and marked increases in EEG electrical activity. Unless anaesthesia is provided during CPB, it is during rewarming that patients will become aware and this recognised phenomenon is harrowingly documented by Thomas and Evans. Considering their failure to administer general anaesthesia, it is surprising that only one patient in 13 had recall. Recall indicates a very high level of consciousness and awareness can occur without recall. That reflex movement in response to painful stimulus indicates a level of consciousness close to awareness and that the level of anaesthesia requires to be deepened is a perceived truth. The use of neuromuscular blocking agents by Evans and Thomas, though a common clinical practice, masks this much-valued indication of anaesthetic depth. I would suggest that movement is a more conservative, reliable and sensitive measure of awareness than recall or lower oesophageal sphincter contractility and one that has been used previously in cardiac anaesthesia (2). If Thomas and Evans had used this method, their incidence of awareness would have been much higher. Patients rightly expect that during general anaesthesia they will be unconscious, not just in a state of analgesia. Not to administer some form of general anaesthesia during CPB is unacceptable. For anaesthetists not to strive to provide anaesthesia has serious ethical and medicolegal implications. R PETER ALS1ON FFARCS Lecturer in Anaesthesia University of Glasgow Glasgow Royal Infirmary
technically awkward manoeuvre of manipulating the anvil attached to the gun into the lower oesophagus after inserting the pursestring is avoided. The separated anvil (with anvil shaft) fits easily into the lower oesophagus allowing the pursestring sutures to be placed accurately with improved access. One word of warning however. During the course of manipulation, pressure on the release knob on the anvil can cause it to separate from the anvil shaft and consequently the staples will fire against a floating anvil and not secure the anastomosis. One should be suspicious of a problem if no resistance is felt on turning the wingnut, even when the green approximation dot appears. The awkward situation may be salvaged by manipulating the anvil shaft back onto the anvil while it is still in the oesophagus. This may be difficult, however, and may require division of the crura to gain better access to the posterior mediastinum. M H JAMISON FRCS Consultant Surgeon Gwynedd District General Hospital Bangor
Intraoperative assessment of lymph node involvement in gastric carcinoma Accurate intraoperative staging of lymph nodes in gastric cancer may well be of no therapeutic importance. Mr Park and his colleagues (Annals, September 1989, vol 71, p324) have confirmed our earlier finding (1) that lymph node spread is usually overestimated by the surgeon. However, whether this matters is debatable because most surgeons ignore the degree of apparent lymph node involvement in deciding to resect and in choosing the type of resection. Node staging only needs to be accurate if it is used to select patients for radical lymphadenectomy (as practised in Japan) because an R2 gastrectomy, which includes the second tier of nodes, causes much greater morbidity than the simpler R1 operation (2). Whether the more radical operation improves survival is unknown. Only if it does so will Mr Park be correct in recommending intraoperative node cytology or histology to achieve accurate staging. M V MADDEN FRCS Senior Lecturer, Department of Surgery D M DENT ChM FRCS
Associate Professor, Department of Surgery S K PRICE MRCPath Senior Lecturer, Department of Pathology
References 1 Patey R, Alston RP. Anaesthetic practice during cardiopulmonary bypass: A UK Survey (unpublished data). 2 Hug CC, Hall RI, Angert KC, Reeder DA, Moldenhauer CC. Alfentanil plasma concentration v effect relationships in cardiac surgical patients. Br 7 Anaesth 1988;61:435-60.
An improved technique for oesophagojejunal anastomosis using the EEA Premium stapling gun In their article (Annals, September 1989, vol 71, p322) Messrs Brough and Tweedle emphasise the very real advantages of the detachable anvil of the EEA Premium stapling gun. The
Groote Schuur Hospital Cape Town, South Africa
References I Madden MV, Price SK, Learmonth Genevieve M, Dent DM. Surgical staging of gastric carcinoma: sources and consequences of error. Br Jr Surg 1987;74:119-21. 2 Dent DM, Madden MV, Price SK. Randomized comparison of R1 and R2 gastrectomy for gastric carcinoma. Br3J Surg 1988;75: 110-12.
Comment
of analysis. Of questionnaires that we have examined to date, all (100) have indicated that the anaesthetist routinely administers one or more anaesthetic agents during CPB. Undoubtedly, there are occasions during cardiac anaesthesia when lifethreatening cardiovascular collapse may occur and it can be argued that the level of anaesthesia should be lightened to eliminate any possible adverse effects that the anaesthetic agents may have on the cardiovascular system. These occasions can occur before, and more frequently after, CPB. This is not the case during CPB when the circulation is mechanically supported. Thus, there can be no reason why some form of anaesthesia should not be administered, whether intravenous, opioid or volatile anaesthetic agent, during CPB. Hypothermia, without doubt, produces unconsciousness, but rewarming commences long before the end of CPB and is associated with immediate and marked increases in EEG electrical activity. Unless anaesthesia is provided during CPB, it is during rewarming that patients will become aware and this recognised phenomenon is harrowingly documented by Thomas and Evans. Considering their failure to administer general anaesthesia, it is surprising that only one patient in 13 had recall. Recall indicates a very high level of consciousness and awareness can occur without recall. That reflex movement in response to painful stimulus indicates a level of consciousness close to awareness and that the level of anaesthesia requires to be deepened is a perceived truth. The use of neuromuscular blocking agents by Evans and Thomas, though a common clinical practice, masks this much-valued indication of anaesthetic depth. I would suggest that movement is a more conservative, reliable and sensitive measure of awareness than recall or lower oesophageal sphincter contractility and one that has been used previously in cardiac anaesthesia (2). If Thomas and Evans had used this method, their incidence of awareness would have been much higher. Patients rightly expect that during general anaesthesia they will be unconscious, not just in a state of analgesia. Not to administer some form of general anaesthesia during CPB is unacceptable. For anaesthetists not to strive to provide anaesthesia has serious ethical and medicolegal implications. R PETER ALS1ON FFARCS Lecturer in Anaesthesia University of Glasgow Glasgow Royal Infirmary
technically awkward manoeuvre of manipulating the anvil attached to the gun into the lower oesophagus after inserting the pursestring is avoided. The separated anvil (with anvil shaft) fits easily into the lower oesophagus allowing the pursestring sutures to be placed accurately with improved access. One word of warning however. During the course of manipulation, pressure on the release knob on the anvil can cause it to separate from the anvil shaft and consequently the staples will fire against a floating anvil and not secure the anastomosis. One should be suspicious of a problem if no resistance is felt on turning the wingnut, even when the green approximation dot appears. The awkward situation may be salvaged by manipulating the anvil shaft back onto the anvil while it is still in the oesophagus. This may be difficult, however, and may require division of the crura to gain better access to the posterior mediastinum. M H JAMISON FRCS Consultant Surgeon Gwynedd District General Hospital Bangor
Intraoperative assessment of lymph node involvement in gastric carcinoma Accurate intraoperative staging of lymph nodes in gastric cancer may well be of no therapeutic importance. Mr Park and his colleagues (Annals, September 1989, vol 71, p324) have confirmed our earlier finding (1) that lymph node spread is usually overestimated by the surgeon. However, whether this matters is debatable because most surgeons ignore the degree of apparent lymph node involvement in deciding to resect and in choosing the type of resection. Node staging only needs to be accurate if it is used to select patients for radical lymphadenectomy (as practised in Japan) because an R2 gastrectomy, which includes the second tier of nodes, causes much greater morbidity than the simpler R1 operation (2). Whether the more radical operation improves survival is unknown. Only if it does so will Mr Park be correct in recommending intraoperative node cytology or histology to achieve accurate staging. M V MADDEN FRCS Senior Lecturer, Department of Surgery D M DENT ChM FRCS
Associate Professor, Department of Surgery S K PRICE MRCPath Senior Lecturer, Department of Pathology
References 1 Patey R, Alston RP. Anaesthetic practice during cardiopulmonary bypass: A UK Survey (unpublished data). 2 Hug CC, Hall RI, Angert KC, Reeder DA, Moldenhauer CC. Alfentanil plasma concentration v effect relationships in cardiac surgical patients. Br 7 Anaesth 1988;61:435-60.
An improved technique for oesophagojejunal anastomosis using the EEA Premium stapling gun In their article (Annals, September 1989, vol 71, p322) Messrs Brough and Tweedle emphasise the very real advantages of the detachable anvil of the EEA Premium stapling gun. The
Groote Schuur Hospital Cape Town, South Africa
References I Madden MV, Price SK, Learmonth Genevieve M, Dent DM. Surgical staging of gastric carcinoma: sources and consequences of error. Br Jr Surg 1987;74:119-21. 2 Dent DM, Madden MV, Price SK. Randomized comparison of R1 and R2 gastrectomy for gastric carcinoma. Br3J Surg 1988;75: 110-12.
