Intentional Hemodilution, Biblthca Haemat., Νο. 41 ed. by K. ΜΕS Μετt and H. SCΗ Μn)-ScΗöΝ ulκ, pp. 270-277 (Karger, Basel 1975)
Hemodilution in Hip Surgery RICÁRDO VELA Department of Anaesthesia and Reanimation, Sanitary City `La Paz', Madrid
I. Introduction
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In our daily work dealing with elective orthopedic and emergency surgery from traumatic accidents, as we have gained experience in the treatment of acute hypovolemic states, we have come, step by step and nearly unaware, to `hemodilutíon', mainly pushed by the deficient results and the important risks involved in blood transfusion as replacement therapy, mostly when the volume to be replaced amounts to 500/0 of the patient's own volume. Programed blood transfusion for surgery has become, in these last years, unnecessary in a great number of cases to maintain the hemodynanúc state during surgical procedures, as macromolecular solutions and dextrans became better known and used more and more for that purpose. The management of some patients of the Jehovah's Witness sect showed us that the previously low levels (considerated as forbidden) of hemoglobin and hematocrit were surprisingly well tolerated by the patients. If we add to these considerations the prophylactic effects of the solutions of dextran on thromboembolic disease, related to a decrease and inhibition of thrombocyte adhesiveness and aggregation and the stenoplastic effect on platelets and inhibition of prothrombin activation, as GRUBER stated in 1970, the justificative use of clinical hemodilution is quite reasonable. Hemodilution, therefore, has proved to be an unphysiologic state surprisingly well tolerated by the patients, that affords: (1) a decreased blood viscosity as a rheologic effect; (2) a better and more complete distribution of the blood flow to the tissues as a hemodynamic effect, and (3) an
271
VELA Charntey 114
Thompson 38
Type of prosthesis
Fig. 1. Type of prosthesis.
antithrombotic effect, as secondary action to the above, to which is added that proper one afforded by dextran solutions. ΙΙ. Method and Discussion
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Hip replacement surgery offers problems during the surgical act, i.e. hypovolemic and hypotensive states due to hemorrhage and to the toxicity of the plastic material used to cement the prosthetic parts to bones. From the patient's aspect, the age and previous pathology in which often appears a long treatment with corticoids, and the bronchi- and pneumopathies therewith associated, are the common clinical states to be dealt with. We have used approximately one-third `hemodilutíon', i.e. as low as 10g0 /ο and 300/0 of the hemoglobin and hematocrit values, respectively, in 220 cases of hip prosthesis, of which 134 cases (60.9°/ο) were women and 86 (390/i) men. From figure 1 we can see that the Charnley method has been used by the surgical teams in more than 500/0 of all cases. The age of patients is distributed by decades as in figure 2. The youngest patient was 24 years old and 'vas a traumatic road accident case. The oldest was a woman of 89 years.
272
VELA 79
20-30
30-40
40-50
50-60
60 - 70
70-80
80-90
Age, years
Fig. 2. Age distribution of patients in decades.
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The general condition and the associated pathology were: (1) in good condition, 70 cases (31.40/0), and (2) associated pathology, 150 cases (68.60/x). Associated pathologies were distributed as follows: (1) bronchopneumopathies, 63 cases (42.00/ο); (2) cardiac disease, 23 cases (15.30/0); (3) obesity, 37 cases (24.60/o), and (4) diabetes, 27 cases (18.00/0). The aged patient has no elasticity or reactive capacity of his vascular beds to compensate blood losses during any clinical situation. Hypovolemic states and vasoconstrictive conditions of the microcirculation are badly tolerated by the heart, brain and kidney of these patients. Therefore, we must maintain the blood volume within normal limits to avoid any further deterioration. The management of these cases requires avoidances of catecholamine release during surgery and in the immediate postoperative period. This commands an anesthetic procedure that affords a quiet and calm neurovegetative state with enough analgesic protection to avoid the autonomic responses to unconscious pain and maintain a clinical anesthetic state as light as possible. Anesthetic techniques have been dealt with in the following way: premedication is given slowly by the intravenous route 5 min prior to the anesthetic induction. We have used Diazepam at doses from 10 to 20 mg, and Haloperidol from 2.5 to 5 mg, according to the age and weight of the patient. In aged people this premedication becomes actually a true induction for anesthesia. The induction of anesthesia was done by the administration of a barbiturate such as Tiamilal or Thiopentone given addition-
Hemodilution in Hip Surgery
273
DEXTRAN
Fig. 3. Amount of dextran and whole blood during surgery.
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ally, very slowly at small doses never exceeding 200 mg, followed by a routine dose of Succinylcholine, just to intubate the patient and to connect him to the anesthetic apparatus. Then the anesthesia is maintained by 120/02, Dextromoramide and Fentanyl being the analgesic drugs and D-tubocurarine the relaxant used. The generous use of analgesic drugs during anesthetic and surgical procedures in order to maintain an open circulation and an active blood flow, required the artificial ventilation of the patient's lungs during operation. All patients but 4 were breathing spontaneously at the end of the operation and nearly awoke on the table. In all the cases we have used, as replacement fluids, dextran 70 and 40 solutions in saline, and in order to avoid dehydration due to the hyperoncotic properties of these macromolecular solutions, we have administered electrolyte and glucose solutions alike. When blood transfusion is required during the operation we add prophylactically 250 ml of sodium bicarbonate solution, of 1.40/ (1/6 molar or 167 mEq/1 of each anion). As soon as the operation starts, we initiate dextran administration, the rate of drip according to blood losses and the blood pressure of the patient, who is under electrocardioscopic and plethysmographic control. The central venous pressure is measured regularly and, to ascertain clinically the state of the microcirculation, we also use the old test of `capillary refill time'.
VELA
274 45=15
30=10-
15= 5-
0
+1 +2 PREOPERATIVE Ι OPERATIVE POSTOPERATIVE
+3
+4
+6
+6
+7
Fig. 4. Postoperative evolution of hemoglobin and hematocrit value (ordinate hct °/o, hb g °/ο, abscissa: days).
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As the operation progresses we give up to 1,000 ml of dextran 70 solution to maintain the hemodynamic state. At this moment we test the blood for hemoglobin and hematocrit values before follow-up. If these values are above 10 gο/ο and 300/0, respectively, we continue giving dextran up to 1,500 ml and then a new test determines our further procedures. When these values are below 10 g°/ο and 300 /ο and the volemic requirements persist, we start to give previously cross-matched whole blood. As soon as the hematometric values rise from the above figures we stop the blood transfusion and again give dextran 40 or balanced electrolyte solutions according to cardiovascular activity. The data of transfusion and dextran infusion during surgery are shown in figure 3. From these figures it is obvious that in 53 cases (240/o) we did not use any blood at all. In 167 cases (760/0) we employed blood. Of these we gave blood for volume replacement in 88 cases (400/0) and to restore the hematometric values in 79 cases (35.90/0). In the immediate postoperative period the incidence of blood transfusion has been around one-third. In 68 cases (30.9°/ο) we transfused to avoid further decrease of hematometric values, due to losses by drainage. In 8 cases (3.6°/0) we had problems of continuing hemorrhage for 24 h
Hemodilution
in Hip Surgery
275
and had to give blood to restore the cardiovascular state. We lost one patient, but his death cannot be related to the hemodilution technique used. In the patient group receiving 1,500 ml of dextran we observed in 43 cases (19.50/0) a persistent bleeding without clinical significance during the first 24 h. During the first 3 days of the postoperative period we try to keep the hemoglobin and hematocrit values around 10 g0/ ο and 300/0, respectively, avoiding blood transfusion, but any decrease below these figures has been compensated with whole blood or concentrated red cells. During this time we maintain a continuous fluid therapy in which we include 500 ml of dextran 70 solution. From the third day onwards we stop the fluid therapy, but continue giving 500 ml daily dextran 70 from 7 to 10 days. On the fourth day we transfer the patients to the surgical wards. We also used for the first 24 h oxygen therapy (by mask) in order to maintain the p02ι as we know that all general anesthetics increase, even under artificial ventilation, the physiological shunt resulting in a decrease of the Ρ02 . By giving oxygen we keep the patient out of a potential hypoxia induced by general anesthetics and hemodilution. We have not observed any significant modification of the coagulating time, and the prothrombine index was never below 700 /0. The fibrinogen values have been maintained, in spite of hemodilution within the lower ranges of normal. This method used for hemodilution seems to us to be simple, efficient and safe, and we are satisfied with it. What is more important is that the surgical teams had no complaints after the first cases. We must realise that to accept hemoglobin and hematocrit values of only 2/3 from normal during and after surgery needs a considerable change of the clinicians' mind. Reference U. F.: Profilaxis de las tromboembolias por el Macrodex (dextrano 70). Actas del Simp. Int. sobre `Los Plasma Expanders y sus Aplicaciones Terapeuticas', pp. 25, 26 (Diana, Madrid 1970).
GRUBER,
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Dr. R. VaLA, Department of Anesthesia and Reanimation, Sanitary City `La Paz', Madrid (Spain)
276
VELA
Discussion Moderator: K. MESSIER
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D. H. LEWIS: Dr. VEI.λ, when Dr. PETER in Mannheim began his studies, he set 60 years as an age limit, which Ι gather he has abandoned. 14e hasn't any age limit in his patients now. On the other hand, Dr. BERGEIrz pointed out that the severe problem with thromboembolism is in patients over the age of 70. If I understand correctly, from your figures concerning the age distribution, more than half of your patients were over the age of 60 and more than a quarter of your patients were over the age of 70. Now my question is, have you seen any more problems in these people than in the younger ones? R. VELA: Well, I have seen problems due to the age of these people. As I pointed out, they have an associated pathology and therefore we must expect from them more problems than from the younger ones. D. H. LEWIS: Have you seen complications because of hemodilution in this age group, which you did not see in the younger age group? R. VELA: Again, the problems we have met in older people are depending more on the general condition due to their age, than to the hemodilution technique described. Of course, in the first cases we selected younger patients without associated pathology; we restricted the indications and excluded all patients with myocardial problems and electrocardiographic signs of ischemia, but not the hypertensive states, except decompensated hypertonus. But we have not found troubles related to the hemodilution technique used, probably because we have been very careful with volume replacement to avoid any hypovolemia. D. H. LEWIS: You mentioned that the surgeons had no complaints. I wonder, did the patients have any complaints? R. VELA: I feel lucky to attend this meeting because I have heard and seen wonderful animal experiments and wonderful results in patients, but nothing has been said about how these patients feel and what they think. Therefore, I am glad that Dr. LEWJS asks this question. According to my experience, the patients complaints are related mostly to the prolonged stay in the recovery room, and they ask to be discharged earlier to their wards or rooms. The rest of complaints are configuring the normal picture of a postoperative period. We have, however, one patient cornplaíníng of tiredness; this was a 72-year-old lady in whom we pushed hemodilution and accidentally a hemoglobin concentration of only 4 g°/° was reached. In spite of her good condition she complained to feel very tired. Tiredness and otherwise unexplicable tachycardia are indicative for us to replace red cells by packed cells or whole blood. K. MESSIER: We had the impression that our dogs were tired too when acutely taken down to a hemoglobin of 2.8 g°/°. M. B. LAVER: I think, we should consider a low hemoglobin level preoperatively only as a relative contraindication to the technique of preoperative hemodilution because, as I mentioned, in my own experience, when that happens I will frequently give the patient packed cells but remove the patients whole blood; so I might have the additional plasma with all the clotting factors which I can give back to the patient after surgery or after the massive blood loss.
Hemodilution in Hip Surgery
277
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K. MESSMER Dr. LAVER, would you please comment on your own experience as far as the hepatitis risk with packed washed red cells versus whole blood is concerned. Is there a significant difference or not? M. B. LAVER: I am not the best qualified person to answer this question, because our hospital blood bank has its own pool of volunteer donors. It has been suggested that the administration of packed red cells will reduce the incidence of hepatitis, but I am not aware of sound data to substantiate it. Someone else may be able to comment more authoritatively on the subject. K. PETER: I just want to come back to what Dr. Lεωτs said. We did not generally limit the age for hemodilution to 60 years: this was only done in the study I reported here. Usually we hemodilute also elderly patients, only in the present study dealing with 25 patients the age was limited to 60 years. D. Η. LEWIS: I obviously misunderstood Dr. PETER. I thought the study was just done in this group only. But the decisive point here is that there is really no age limitation for this form of treatment.
Hemodilution in Hip Surgery RICÁRDO VELA Department of Anaesthesia and Reanimation, Sanitary City `La Paz', Madrid
I. Introduction
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In our daily work dealing with elective orthopedic and emergency surgery from traumatic accidents, as we have gained experience in the treatment of acute hypovolemic states, we have come, step by step and nearly unaware, to `hemodilutíon', mainly pushed by the deficient results and the important risks involved in blood transfusion as replacement therapy, mostly when the volume to be replaced amounts to 500/0 of the patient's own volume. Programed blood transfusion for surgery has become, in these last years, unnecessary in a great number of cases to maintain the hemodynanúc state during surgical procedures, as macromolecular solutions and dextrans became better known and used more and more for that purpose. The management of some patients of the Jehovah's Witness sect showed us that the previously low levels (considerated as forbidden) of hemoglobin and hematocrit were surprisingly well tolerated by the patients. If we add to these considerations the prophylactic effects of the solutions of dextran on thromboembolic disease, related to a decrease and inhibition of thrombocyte adhesiveness and aggregation and the stenoplastic effect on platelets and inhibition of prothrombin activation, as GRUBER stated in 1970, the justificative use of clinical hemodilution is quite reasonable. Hemodilution, therefore, has proved to be an unphysiologic state surprisingly well tolerated by the patients, that affords: (1) a decreased blood viscosity as a rheologic effect; (2) a better and more complete distribution of the blood flow to the tissues as a hemodynamic effect, and (3) an
271
VELA Charntey 114
Thompson 38
Type of prosthesis
Fig. 1. Type of prosthesis.
antithrombotic effect, as secondary action to the above, to which is added that proper one afforded by dextran solutions. ΙΙ. Method and Discussion
Downloaded by: Université de Paris 193.51.85.197 - 1/30/2020 7:32:34 AM
Hip replacement surgery offers problems during the surgical act, i.e. hypovolemic and hypotensive states due to hemorrhage and to the toxicity of the plastic material used to cement the prosthetic parts to bones. From the patient's aspect, the age and previous pathology in which often appears a long treatment with corticoids, and the bronchi- and pneumopathies therewith associated, are the common clinical states to be dealt with. We have used approximately one-third `hemodilutíon', i.e. as low as 10g0 /ο and 300/0 of the hemoglobin and hematocrit values, respectively, in 220 cases of hip prosthesis, of which 134 cases (60.9°/ο) were women and 86 (390/i) men. From figure 1 we can see that the Charnley method has been used by the surgical teams in more than 500/0 of all cases. The age of patients is distributed by decades as in figure 2. The youngest patient was 24 years old and 'vas a traumatic road accident case. The oldest was a woman of 89 years.
272
VELA 79
20-30
30-40
40-50
50-60
60 - 70
70-80
80-90
Age, years
Fig. 2. Age distribution of patients in decades.
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The general condition and the associated pathology were: (1) in good condition, 70 cases (31.40/0), and (2) associated pathology, 150 cases (68.60/x). Associated pathologies were distributed as follows: (1) bronchopneumopathies, 63 cases (42.00/ο); (2) cardiac disease, 23 cases (15.30/0); (3) obesity, 37 cases (24.60/o), and (4) diabetes, 27 cases (18.00/0). The aged patient has no elasticity or reactive capacity of his vascular beds to compensate blood losses during any clinical situation. Hypovolemic states and vasoconstrictive conditions of the microcirculation are badly tolerated by the heart, brain and kidney of these patients. Therefore, we must maintain the blood volume within normal limits to avoid any further deterioration. The management of these cases requires avoidances of catecholamine release during surgery and in the immediate postoperative period. This commands an anesthetic procedure that affords a quiet and calm neurovegetative state with enough analgesic protection to avoid the autonomic responses to unconscious pain and maintain a clinical anesthetic state as light as possible. Anesthetic techniques have been dealt with in the following way: premedication is given slowly by the intravenous route 5 min prior to the anesthetic induction. We have used Diazepam at doses from 10 to 20 mg, and Haloperidol from 2.5 to 5 mg, according to the age and weight of the patient. In aged people this premedication becomes actually a true induction for anesthesia. The induction of anesthesia was done by the administration of a barbiturate such as Tiamilal or Thiopentone given addition-
Hemodilution in Hip Surgery
273
DEXTRAN
Fig. 3. Amount of dextran and whole blood during surgery.
Downloaded by: Université de Paris 193.51.85.197 - 1/30/2020 7:32:34 AM
ally, very slowly at small doses never exceeding 200 mg, followed by a routine dose of Succinylcholine, just to intubate the patient and to connect him to the anesthetic apparatus. Then the anesthesia is maintained by 120/02, Dextromoramide and Fentanyl being the analgesic drugs and D-tubocurarine the relaxant used. The generous use of analgesic drugs during anesthetic and surgical procedures in order to maintain an open circulation and an active blood flow, required the artificial ventilation of the patient's lungs during operation. All patients but 4 were breathing spontaneously at the end of the operation and nearly awoke on the table. In all the cases we have used, as replacement fluids, dextran 70 and 40 solutions in saline, and in order to avoid dehydration due to the hyperoncotic properties of these macromolecular solutions, we have administered electrolyte and glucose solutions alike. When blood transfusion is required during the operation we add prophylactically 250 ml of sodium bicarbonate solution, of 1.40/ (1/6 molar or 167 mEq/1 of each anion). As soon as the operation starts, we initiate dextran administration, the rate of drip according to blood losses and the blood pressure of the patient, who is under electrocardioscopic and plethysmographic control. The central venous pressure is measured regularly and, to ascertain clinically the state of the microcirculation, we also use the old test of `capillary refill time'.
VELA
274 45=15
30=10-
15= 5-
0
+1 +2 PREOPERATIVE Ι OPERATIVE POSTOPERATIVE
+3
+4
+6
+6
+7
Fig. 4. Postoperative evolution of hemoglobin and hematocrit value (ordinate hct °/o, hb g °/ο, abscissa: days).
Downloaded by: Université de Paris 193.51.85.197 - 1/30/2020 7:32:34 AM
As the operation progresses we give up to 1,000 ml of dextran 70 solution to maintain the hemodynamic state. At this moment we test the blood for hemoglobin and hematocrit values before follow-up. If these values are above 10 gο/ο and 300/0, respectively, we continue giving dextran up to 1,500 ml and then a new test determines our further procedures. When these values are below 10 g°/ο and 300 /ο and the volemic requirements persist, we start to give previously cross-matched whole blood. As soon as the hematometric values rise from the above figures we stop the blood transfusion and again give dextran 40 or balanced electrolyte solutions according to cardiovascular activity. The data of transfusion and dextran infusion during surgery are shown in figure 3. From these figures it is obvious that in 53 cases (240/o) we did not use any blood at all. In 167 cases (760/0) we employed blood. Of these we gave blood for volume replacement in 88 cases (400/0) and to restore the hematometric values in 79 cases (35.90/0). In the immediate postoperative period the incidence of blood transfusion has been around one-third. In 68 cases (30.9°/ο) we transfused to avoid further decrease of hematometric values, due to losses by drainage. In 8 cases (3.6°/0) we had problems of continuing hemorrhage for 24 h
Hemodilution
in Hip Surgery
275
and had to give blood to restore the cardiovascular state. We lost one patient, but his death cannot be related to the hemodilution technique used. In the patient group receiving 1,500 ml of dextran we observed in 43 cases (19.50/0) a persistent bleeding without clinical significance during the first 24 h. During the first 3 days of the postoperative period we try to keep the hemoglobin and hematocrit values around 10 g0/ ο and 300/0, respectively, avoiding blood transfusion, but any decrease below these figures has been compensated with whole blood or concentrated red cells. During this time we maintain a continuous fluid therapy in which we include 500 ml of dextran 70 solution. From the third day onwards we stop the fluid therapy, but continue giving 500 ml daily dextran 70 from 7 to 10 days. On the fourth day we transfer the patients to the surgical wards. We also used for the first 24 h oxygen therapy (by mask) in order to maintain the p02ι as we know that all general anesthetics increase, even under artificial ventilation, the physiological shunt resulting in a decrease of the Ρ02 . By giving oxygen we keep the patient out of a potential hypoxia induced by general anesthetics and hemodilution. We have not observed any significant modification of the coagulating time, and the prothrombine index was never below 700 /0. The fibrinogen values have been maintained, in spite of hemodilution within the lower ranges of normal. This method used for hemodilution seems to us to be simple, efficient and safe, and we are satisfied with it. What is more important is that the surgical teams had no complaints after the first cases. We must realise that to accept hemoglobin and hematocrit values of only 2/3 from normal during and after surgery needs a considerable change of the clinicians' mind. Reference U. F.: Profilaxis de las tromboembolias por el Macrodex (dextrano 70). Actas del Simp. Int. sobre `Los Plasma Expanders y sus Aplicaciones Terapeuticas', pp. 25, 26 (Diana, Madrid 1970).
GRUBER,
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Dr. R. VaLA, Department of Anesthesia and Reanimation, Sanitary City `La Paz', Madrid (Spain)
276
VELA
Discussion Moderator: K. MESSIER
Downloaded by: Université de Paris 193.51.85.197 - 1/30/2020 7:32:34 AM
D. H. LEWIS: Dr. VEI.λ, when Dr. PETER in Mannheim began his studies, he set 60 years as an age limit, which Ι gather he has abandoned. 14e hasn't any age limit in his patients now. On the other hand, Dr. BERGEIrz pointed out that the severe problem with thromboembolism is in patients over the age of 70. If I understand correctly, from your figures concerning the age distribution, more than half of your patients were over the age of 60 and more than a quarter of your patients were over the age of 70. Now my question is, have you seen any more problems in these people than in the younger ones? R. VELA: Well, I have seen problems due to the age of these people. As I pointed out, they have an associated pathology and therefore we must expect from them more problems than from the younger ones. D. H. LEWIS: Have you seen complications because of hemodilution in this age group, which you did not see in the younger age group? R. VELA: Again, the problems we have met in older people are depending more on the general condition due to their age, than to the hemodilution technique described. Of course, in the first cases we selected younger patients without associated pathology; we restricted the indications and excluded all patients with myocardial problems and electrocardiographic signs of ischemia, but not the hypertensive states, except decompensated hypertonus. But we have not found troubles related to the hemodilution technique used, probably because we have been very careful with volume replacement to avoid any hypovolemia. D. H. LEWIS: You mentioned that the surgeons had no complaints. I wonder, did the patients have any complaints? R. VELA: I feel lucky to attend this meeting because I have heard and seen wonderful animal experiments and wonderful results in patients, but nothing has been said about how these patients feel and what they think. Therefore, I am glad that Dr. LEWJS asks this question. According to my experience, the patients complaints are related mostly to the prolonged stay in the recovery room, and they ask to be discharged earlier to their wards or rooms. The rest of complaints are configuring the normal picture of a postoperative period. We have, however, one patient cornplaíníng of tiredness; this was a 72-year-old lady in whom we pushed hemodilution and accidentally a hemoglobin concentration of only 4 g°/° was reached. In spite of her good condition she complained to feel very tired. Tiredness and otherwise unexplicable tachycardia are indicative for us to replace red cells by packed cells or whole blood. K. MESSIER: We had the impression that our dogs were tired too when acutely taken down to a hemoglobin of 2.8 g°/°. M. B. LAVER: I think, we should consider a low hemoglobin level preoperatively only as a relative contraindication to the technique of preoperative hemodilution because, as I mentioned, in my own experience, when that happens I will frequently give the patient packed cells but remove the patients whole blood; so I might have the additional plasma with all the clotting factors which I can give back to the patient after surgery or after the massive blood loss.
Hemodilution in Hip Surgery
277
Downloaded by: Université de Paris 193.51.85.197 - 1/30/2020 7:32:34 AM
K. MESSMER Dr. LAVER, would you please comment on your own experience as far as the hepatitis risk with packed washed red cells versus whole blood is concerned. Is there a significant difference or not? M. B. LAVER: I am not the best qualified person to answer this question, because our hospital blood bank has its own pool of volunteer donors. It has been suggested that the administration of packed red cells will reduce the incidence of hepatitis, but I am not aware of sound data to substantiate it. Someone else may be able to comment more authoritatively on the subject. K. PETER: I just want to come back to what Dr. Lεωτs said. We did not generally limit the age for hemodilution to 60 years: this was only done in the study I reported here. Usually we hemodilute also elderly patients, only in the present study dealing with 25 patients the age was limited to 60 years. D. Η. LEWIS: I obviously misunderstood Dr. PETER. I thought the study was just done in this group only. But the decisive point here is that there is really no age limitation for this form of treatment.
