1914
December 1992 Am J Obstet Gyneco1
Letters
with the instrument a little and were at first glance not dissatisfied, although we remain critical. The efficacy and effectiveness of the system need to be investigated in an additional number of well-designed studies. In this regard Dawes and Redman should accept and even be pleased that others than the designers of the basic elements (software) in the System 8000 give their time and energy to increase knowledge about this special technique, which represents just one way to quantitate fetal heart rhythm. H.P. van Geijn, MD, R. Mantel, MD, 1.A.P. Ververs, MD, and FJ.A. Copray Department of Obstetrics and Gynecology, Academish Ziekenhuis Vriji Universiteit, De Boelelaan 1117, 1007 MB Amsterdam, The Netherlands
inhibitor deficiencies (antithrombin, protein S, or protein C) or in women with prosthetic valves, however, the continuous anticoagulation might be of therapeutic value. Floyd et al. deserve credit for again bringing out the good acceptance by the women with this method. Lennart Hahn, MD, PhD Department of Obstetrics and Gynecology, East Hospital, S 416 85, Gothenburg, Sweden REFERENCES
1. Barss VA, Schwartz PA, Green MF, Phillippe M, Saltzman D,
Frigoletteo FD. Use of the subcutaneous heparin pump during pregnancy.] Reprod Med 1985;30:899-901. 2. Hahn L. Pulsatile heparin administration in pregnancy: a new approach. AM] OBSTET GYNECOL 1986;155:283-7. 3. Hellgren M, Hahn L, Dahlman T. Thromboprophylaxis during pregnancy [Letter]. AM] OBSTET GYNECOL 1990;162: 1338-9.
Heparin administration with a pump during pregnancy To the Editors: The article by Floyd et al. (Floyd RC, Gookin KS, Hess LW, et al. Administration of heparin by subcutaneous infusion with a programmable pump. AM J OBSTET GYNECOL 1991;165:931-3) on anticoagulation during pregnancy deserves some comments. The authors refer to one previous article on "continuous" heparin administration by Barss et al.' in which the subcutaneously placed needle led to bleeding complications in a large percentage. However, Floyd et al. seem to have completely ignored another article on pulsatile heparin administration in pregnancy in which 15 women used a programmable pump to deliver heparin by either the intravenous or the subcutaneous route for ~ 34 weeks. 2 In that paper the anticoagulant effect was monitored on the basis of anti-Factor Xa measurements at defined time intervals from the subcutaneous injection or during one pump interval. In the paper by Floyd et al. no mention is made of these intervals. Moreover, the use of thromboplastin times to monitor heparin requirements is too insensitive and should be replaced by anti-Factor Xa measurements. The authors seem to be satisfied with the greater amount of heparin used in the pump group and believe that this was the result of better patient compliance. The mean daily dose of 14,000 U in the subcutaneous group is a very low dose, which means that at least some of these women were not adequately anticoagulated. 3 If that in turn was caused by bad compliance, these women might have benefited more from home visits than the pump group! A possible advantage with the programmable pump compared with the subcutaneous injections is the possibility to decrease the total dose of heparin! This is because the side effects of heparin are believed to be dose-dependent. Another advantage with the pump is that it gives an adequate anticoagulation day and night, whereas subcutaneous injections give varying levels of anti-Factor Xa that are sometimes undetectable after 6 to 8 hours! In most women this seems to be of no importance. 3 In women with complicating diseases such as hereditary
Reply To the Editors: Hahn's comments are appreciated. Reference is made to his article' on pulsatile heparin administration and monitoring of serum heparin levels by using anti-Factor Xa assessments. Anti-Factor Xa measurements are sensitive but are expensive and are not readily available in most facilities. The use of thromboplastin times to monitor heparin requirements is accessible to all practicing physicians and is generally accepted as the means of clinically monitoring heparin therapy. In presenting the use of the programmable subcutaneous infusion pump to anticoagulate our patients, we emphasized a protocol that is useful in clinical practice. Hahn also voiced concern about the low dose of heparin used by those in the subcutaneous group. The reduced rate of heparin used in these patients was believed to be caused by poor compliance and was an attempt to prevent overanticoagulation of the patient in the immediate posti~ection period. Use of more frequent injections as recommended in his letter may not be an acceptable solution in many women because of a further decrease in compliance. The suggestion of home nursing visits in patients using subcutaneous injection for anticoagulation does have merit. His mention of heparin-related complications and their dosedependent relationship is well taken; however, in our patients no complications were noted in spite of the larger amounts of heparin used in subjects using the pump. Randall C. Floyd, MD, and John C. Morrison, MD Department of Obstetrics and Gynecology, 2500 North State St., Jackson, MS 39216-4505 REFERENCE
1. Hahn CL. Pulsatile heparin administration in pregnancy: a new approach. AM] OBSTET GYNECOL 1986;155:283-7.
Meconium aspiration syndrome made murkier To the Editors: In their recent publication Katz and Bowes (Katz VL, Bowes WA Jr. Meconium aspiration syndrome: reflections on a murky subject. AM J OBSTET
December 1992 Am J Obstet Gyneco1
Letters
with the instrument a little and were at first glance not dissatisfied, although we remain critical. The efficacy and effectiveness of the system need to be investigated in an additional number of well-designed studies. In this regard Dawes and Redman should accept and even be pleased that others than the designers of the basic elements (software) in the System 8000 give their time and energy to increase knowledge about this special technique, which represents just one way to quantitate fetal heart rhythm. H.P. van Geijn, MD, R. Mantel, MD, 1.A.P. Ververs, MD, and FJ.A. Copray Department of Obstetrics and Gynecology, Academish Ziekenhuis Vriji Universiteit, De Boelelaan 1117, 1007 MB Amsterdam, The Netherlands
inhibitor deficiencies (antithrombin, protein S, or protein C) or in women with prosthetic valves, however, the continuous anticoagulation might be of therapeutic value. Floyd et al. deserve credit for again bringing out the good acceptance by the women with this method. Lennart Hahn, MD, PhD Department of Obstetrics and Gynecology, East Hospital, S 416 85, Gothenburg, Sweden REFERENCES
1. Barss VA, Schwartz PA, Green MF, Phillippe M, Saltzman D,
Frigoletteo FD. Use of the subcutaneous heparin pump during pregnancy.] Reprod Med 1985;30:899-901. 2. Hahn L. Pulsatile heparin administration in pregnancy: a new approach. AM] OBSTET GYNECOL 1986;155:283-7. 3. Hellgren M, Hahn L, Dahlman T. Thromboprophylaxis during pregnancy [Letter]. AM] OBSTET GYNECOL 1990;162: 1338-9.
Heparin administration with a pump during pregnancy To the Editors: The article by Floyd et al. (Floyd RC, Gookin KS, Hess LW, et al. Administration of heparin by subcutaneous infusion with a programmable pump. AM J OBSTET GYNECOL 1991;165:931-3) on anticoagulation during pregnancy deserves some comments. The authors refer to one previous article on "continuous" heparin administration by Barss et al.' in which the subcutaneously placed needle led to bleeding complications in a large percentage. However, Floyd et al. seem to have completely ignored another article on pulsatile heparin administration in pregnancy in which 15 women used a programmable pump to deliver heparin by either the intravenous or the subcutaneous route for ~ 34 weeks. 2 In that paper the anticoagulant effect was monitored on the basis of anti-Factor Xa measurements at defined time intervals from the subcutaneous injection or during one pump interval. In the paper by Floyd et al. no mention is made of these intervals. Moreover, the use of thromboplastin times to monitor heparin requirements is too insensitive and should be replaced by anti-Factor Xa measurements. The authors seem to be satisfied with the greater amount of heparin used in the pump group and believe that this was the result of better patient compliance. The mean daily dose of 14,000 U in the subcutaneous group is a very low dose, which means that at least some of these women were not adequately anticoagulated. 3 If that in turn was caused by bad compliance, these women might have benefited more from home visits than the pump group! A possible advantage with the programmable pump compared with the subcutaneous injections is the possibility to decrease the total dose of heparin! This is because the side effects of heparin are believed to be dose-dependent. Another advantage with the pump is that it gives an adequate anticoagulation day and night, whereas subcutaneous injections give varying levels of anti-Factor Xa that are sometimes undetectable after 6 to 8 hours! In most women this seems to be of no importance. 3 In women with complicating diseases such as hereditary
Reply To the Editors: Hahn's comments are appreciated. Reference is made to his article' on pulsatile heparin administration and monitoring of serum heparin levels by using anti-Factor Xa assessments. Anti-Factor Xa measurements are sensitive but are expensive and are not readily available in most facilities. The use of thromboplastin times to monitor heparin requirements is accessible to all practicing physicians and is generally accepted as the means of clinically monitoring heparin therapy. In presenting the use of the programmable subcutaneous infusion pump to anticoagulate our patients, we emphasized a protocol that is useful in clinical practice. Hahn also voiced concern about the low dose of heparin used by those in the subcutaneous group. The reduced rate of heparin used in these patients was believed to be caused by poor compliance and was an attempt to prevent overanticoagulation of the patient in the immediate posti~ection period. Use of more frequent injections as recommended in his letter may not be an acceptable solution in many women because of a further decrease in compliance. The suggestion of home nursing visits in patients using subcutaneous injection for anticoagulation does have merit. His mention of heparin-related complications and their dosedependent relationship is well taken; however, in our patients no complications were noted in spite of the larger amounts of heparin used in subjects using the pump. Randall C. Floyd, MD, and John C. Morrison, MD Department of Obstetrics and Gynecology, 2500 North State St., Jackson, MS 39216-4505 REFERENCE
1. Hahn CL. Pulsatile heparin administration in pregnancy: a new approach. AM] OBSTET GYNECOL 1986;155:283-7.
Meconium aspiration syndrome made murkier To the Editors: In their recent publication Katz and Bowes (Katz VL, Bowes WA Jr. Meconium aspiration syndrome: reflections on a murky subject. AM J OBSTET
