- Email: [email protected]
Preoperative detection of colon cancer
by regular urinalysis.. If urinalysis is positive for blood, then cytology and cystoscopy should be done. It is no longer safe to ascribe even microscopic haematuria to cancer
NSAID-induced bladder inflammation. Richard J Millard, Simon McCredie Department of Urology, University of New South Wales, Prince Henry Hospital, Sydney, NSW 2036, Australia
1 Trenkwalder P, Eisenlohr H, Prechtel K, Lydtin H. Three
cases
malignant neoplasm, pneumonitis, and pancytopaenia during treatment with low-dose methotrexate. J Clin Invest 1992; 70:
of
951-55.
Preoperative detection of colon cancer SIR-Kitamura and colleagues (March 26, p 789) report the of activated carbon injection as a new method to identify early colon cancer that is invisible during laparoscopic surgery. We acknowledged’ the drawback that the colon cannot be palpated directly to confirm the site of laparoscopically impalpable lesions and recommended contrast radiology to confirm the location of colonoscopically diagnosed lesions before laparoscopically assisted colectomy. Since our original report we have continued to advocate preoperative contrast radiology to confirm the location of colonoscopically diagnosed lesions but have also recommended that if the lesion is small, the injection of India ink at colonoscopy should be used to facilitate localisation at laparoscopy.2 India ink is used because of the intensity and by duration of the tattoo it produces. Methylene blue can also be used but has the disadvantage of lasting for only 24 hours. The colonoscopist cannot predict which section of the bowel circumference will be easily visualised at the time of surgery. A single injection may be adequate for subsequent endoscopic visualisation but may not be the optimum lesion locator at surgery. For this reason, we have recommended that four quadrant circumferential India ink injections should be used.2 We fail to see any advantage of activated carbon over more established methods. We are also concerned as to whether it is necessary, as reported by Kitamura and colleagues, to wait from 3 to 7 days for the activated carbon injection to be visualised at laparoscopy since this would require a second bowel preparation for the unfortunate
use
patient. Arnold D K Hill, A Darzi Department of Surgery, Central
Middlesex Hospital, London NW10 7NS, UK
1 Monson JRT, Darzi A, Carey PD, Guillou PJ. Prospective evaluation of laparoscopic-assisted colectomy in an unselected group of patients. Lancet 1992; 340: 831-33. 2 Hill ADK, Banwell PE, Darzi A. Laparoscopic colonic surgery: the unseen lesion. Min Invasive Ther 1993; 2: 171-72.
Potassium ion depletion filter for blood transfusion
Figure: Potassium ion depletion filter K* rarely exceeds 5 mmol per blood bag.’ This not only takes too much time in emergency transfusion but also makes it impossible to continue to preserve the blood by breaking the sterility of the blood bag. In spite of this, irradiation of blood bags has recently been strongly recommended for the prevention of post-transfusion graftversus-host reactions.2 This treatment increases K+ efflux from red cells,3 but we have no way of knowing the K+ concentration in sealed blood bags. We have developed a transfusion filter that removes K* safely. Sodium polystyrene sulphonate (a strongly acidic cation exchange resin in the S03Na form), which has long been used in the treatment of uraemic hyperkalaemia by irrigation enema, is packed into the usual 150 µm mesh transfusion filter (figure). 25 mL of the resin beads (0-4 mm diameter) can be packed in the usual transfusion filter; the K+ removal capacity is 30 mmol by exchanging the same amount of sodium ion. Our preliminary trial confirmed that K* in 400 mL of blood concentrated in a blood bag (300 mL) in which the K* level exceeded 30 mmol/L (actual amount of K* about 5 mmol) was decreased to less than 10 mmol/L (mean 70% removal, less than 2 mmol per bag) in only one passage through this filter, and that the K+ removal capacity was not decreased even with blood flow rates exceeding 50 mLJmin. A single filter can decrease K* to a safe level in at least three blood bags passing continuously through the filter. This transfusion filter can tolerate autoclave sterilisation and the ion exchange resin is inexpensive.This K* depletion filter will be available for clinical use within the next few years. We are now trying this system with a leucocyte depletion filter. Shoichi Inaba, Noriaki Shirahama
SIR-The potassium ion (K’) level of concentrated red cells and whole blood increases with time since donation. A high concentration of K+ in blood bags may cause not only pain but also cardiac arrest due to transient hyperkalaemia in several clinical situations such as rapid transfusion for massive bleeding and transfusion in neonates or in patients with renal failure. At present, we have only one way to evade the risk of high K+ concentrations-washing blood immediately before transfusion even though the amount of
Blood Transfusion Service, Kyushu University Hospital, 3-1-1, Maidashi, Higashi-ku, Fukuoka, 812, Japan; and Research Development 1-group, Kawasumi Laboratories
Inc, Oita, Japan
1 2 3
Strauss RG. Routinely washing irradiated red cells before transfusion seems unwarranted. Transfusion 1990; 30: 675-77. Perkins HA. Should all blood from related donors be irradiated? Transfusion 1992; 32: 302-03. Brugnara C, Churchill WH. Effect of irradiation on red cell cation content and transport. Transfusion 1992; 32: 246-52.
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NSAID-induced bladder inflammation. Richard J Millard, Simon McCredie Department of Urology, University of New South Wales, Prince Henry Hospital, Sydney, NSW 2036, Australia
1 Trenkwalder P, Eisenlohr H, Prechtel K, Lydtin H. Three
cases
malignant neoplasm, pneumonitis, and pancytopaenia during treatment with low-dose methotrexate. J Clin Invest 1992; 70:
of
951-55.
Preoperative detection of colon cancer SIR-Kitamura and colleagues (March 26, p 789) report the of activated carbon injection as a new method to identify early colon cancer that is invisible during laparoscopic surgery. We acknowledged’ the drawback that the colon cannot be palpated directly to confirm the site of laparoscopically impalpable lesions and recommended contrast radiology to confirm the location of colonoscopically diagnosed lesions before laparoscopically assisted colectomy. Since our original report we have continued to advocate preoperative contrast radiology to confirm the location of colonoscopically diagnosed lesions but have also recommended that if the lesion is small, the injection of India ink at colonoscopy should be used to facilitate localisation at laparoscopy.2 India ink is used because of the intensity and by duration of the tattoo it produces. Methylene blue can also be used but has the disadvantage of lasting for only 24 hours. The colonoscopist cannot predict which section of the bowel circumference will be easily visualised at the time of surgery. A single injection may be adequate for subsequent endoscopic visualisation but may not be the optimum lesion locator at surgery. For this reason, we have recommended that four quadrant circumferential India ink injections should be used.2 We fail to see any advantage of activated carbon over more established methods. We are also concerned as to whether it is necessary, as reported by Kitamura and colleagues, to wait from 3 to 7 days for the activated carbon injection to be visualised at laparoscopy since this would require a second bowel preparation for the unfortunate
use
patient. Arnold D K Hill, A Darzi Department of Surgery, Central
Middlesex Hospital, London NW10 7NS, UK
1 Monson JRT, Darzi A, Carey PD, Guillou PJ. Prospective evaluation of laparoscopic-assisted colectomy in an unselected group of patients. Lancet 1992; 340: 831-33. 2 Hill ADK, Banwell PE, Darzi A. Laparoscopic colonic surgery: the unseen lesion. Min Invasive Ther 1993; 2: 171-72.
Potassium ion depletion filter for blood transfusion
Figure: Potassium ion depletion filter K* rarely exceeds 5 mmol per blood bag.’ This not only takes too much time in emergency transfusion but also makes it impossible to continue to preserve the blood by breaking the sterility of the blood bag. In spite of this, irradiation of blood bags has recently been strongly recommended for the prevention of post-transfusion graftversus-host reactions.2 This treatment increases K+ efflux from red cells,3 but we have no way of knowing the K+ concentration in sealed blood bags. We have developed a transfusion filter that removes K* safely. Sodium polystyrene sulphonate (a strongly acidic cation exchange resin in the S03Na form), which has long been used in the treatment of uraemic hyperkalaemia by irrigation enema, is packed into the usual 150 µm mesh transfusion filter (figure). 25 mL of the resin beads (0-4 mm diameter) can be packed in the usual transfusion filter; the K+ removal capacity is 30 mmol by exchanging the same amount of sodium ion. Our preliminary trial confirmed that K* in 400 mL of blood concentrated in a blood bag (300 mL) in which the K* level exceeded 30 mmol/L (actual amount of K* about 5 mmol) was decreased to less than 10 mmol/L (mean 70% removal, less than 2 mmol per bag) in only one passage through this filter, and that the K+ removal capacity was not decreased even with blood flow rates exceeding 50 mLJmin. A single filter can decrease K* to a safe level in at least three blood bags passing continuously through the filter. This transfusion filter can tolerate autoclave sterilisation and the ion exchange resin is inexpensive.This K* depletion filter will be available for clinical use within the next few years. We are now trying this system with a leucocyte depletion filter. Shoichi Inaba, Noriaki Shirahama
SIR-The potassium ion (K’) level of concentrated red cells and whole blood increases with time since donation. A high concentration of K+ in blood bags may cause not only pain but also cardiac arrest due to transient hyperkalaemia in several clinical situations such as rapid transfusion for massive bleeding and transfusion in neonates or in patients with renal failure. At present, we have only one way to evade the risk of high K+ concentrations-washing blood immediately before transfusion even though the amount of
Blood Transfusion Service, Kyushu University Hospital, 3-1-1, Maidashi, Higashi-ku, Fukuoka, 812, Japan; and Research Development 1-group, Kawasumi Laboratories
Inc, Oita, Japan
1 2 3
Strauss RG. Routinely washing irradiated red cells before transfusion seems unwarranted. Transfusion 1990; 30: 675-77. Perkins HA. Should all blood from related donors be irradiated? Transfusion 1992; 32: 302-03. Brugnara C, Churchill WH. Effect of irradiation on red cell cation content and transport. Transfusion 1992; 32: 246-52.
1223