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Intraoperative blood loss in bimaxillary orthognathic surgery with multisegmental Le Fort I osteotomies and additional procedures
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British Journal of Oral and Maxillofacial Surgery 48 (2010) 276–280
Intraoperative blood loss in bimaxillary orthognathic surgery with multisegmental Le Fort I osteotomies and additional procedures W.B. Kretschmer a,b,∗ , G. Baciut b , Mihaela Bacuit b , W. Zoder a , K. Wangerin a a b
Department of Oral and Maxillofacial Surgery, Marienhospital, Stuttgart, Germany Clinic of Cranio-Maxillofacial Surgery, University of Medicine and Pharmacy, Cluj-Napoca, Romania
Accepted 7 July 2009 Available online 4 August 2009
Abstract Autologous blood donation is not currently recommended by most authors for routine bimaxillary osteotomies. There are few data about bimaxillary procedures with multisegmental maxillary osteotomies. Our aim was to investigate the effect of additional osteotomies and iliac crest grafts on operative blood loss. A total of 225 consecutive patients having bimaxillary multisegmental osteotomies during a three-year period (January 2006–January 2009) were examined to see if their haemoglobin concentration and packed cell volume were reduced. The influence of iliac crest grafts, additional osteotomies (genioplasty, malar osteotomy, iliac crest graft, anterior mandibular segmental osteotomy), operating time, age, and sex were assessed. Neither age nor sex influenced blood loss, whereas operating time correlated significantly with reductions in haemoglobin concentration and packed cell volume. Blood loss was significantly higher in the group who had additional procedures (p 0.001 for haemoglobin concentration and packed cell volume) than in the group who had no additional procedures, whereas there were no significant differences among the three subgroups who had additional procedures (additional osteotomies, iliac crest grafts, or both procedures). Four patients who had additional procedures required transfusion, whereas no blood was given in the group who had no additional procedures. Because the transfusion rate was so low, we could make no general recommendation for preoperative blood donation in such cases. © 2009 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved. Keywords: Blood loss; Orthognathic surgery; Bimaxillary osteotomies; Multisegmental maxillary osteotomy; Additional procedures
Introduction Autologous blood donation is not considered to be essential for bimaxillary orthognathic surgery.1–5 Hypotensive anaesthesia reduces blood loss by more than 40%.6,7 Changes in the criteria for transfusion have also reduced the previously high transfusion rates.1,8,9 However, factors such as segmentation of the maxilla, grafts from the iliac crest, or additional osteotomies raise the likelihood of transfusion significantly.1,2,5,10–12 Operating time is also correlated with ∗
Corresponding author at: Department of Oral and Maxillofacial Surgery, Marienhospital, Stuttgart, Boeheimstr. 37, 70199 Stuttgart, Germany. Tel.: +49 711 6489 8261; fax: +49 711 6489 8262. E-mail address: [email protected] (W.B. Kretschmer).
blood loss, as the studies of Kretschmer et al., Yu et al., and Ueki et al., have shown.5,10,13 Unfortunately there are few data about the “high risk” group of bimaxillary osteotomies with segmentation of the maxilla and additional procedures. We know of no study about the influence of different additional procedures on blood loss in this group. The purpose of the present study was to distinguish factors that led to a high risk of transfusion within the group of bimaxillary osteotomies with segmentation of the maxilla.
Patients and methods The data about 225 consecutive patients (134 women and 91 men aged 16–54 years) who had bimaxillary operations
0266-4356/$ – see front matter © 2009 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
doi:10.1016/j.bjoms.2009.07.011
W.B. Kretschmer et al. / British Journal of Oral and Maxillofacial Surgery 48 (2010) 276–280 Table 1 Maxillary osteotomies (n = 225).
277
Table 3 Groups and subgroups (n = 225).
Type of segmental osteotomy
No. of patients
Group/subgroup
No. of patients
Two-piece Three-piece Four-piece Five-piece
59 163 2 1
No additional procedure Additional procedures Additional osteotomies Iliac crest graft Additional osteotomies and iliac crest graft
132 93 44 29 20
with multisegmental maxillary osteotomies (MMOs) from January 2006 to January 2009 were assessed. Exclusion criteria were the presence of coagulopathy, cleft palate, or craniofacial syndromes. All patients were healthy (American Society of Anesthesiologists grade I). The MMO (Table 1) was done using Bell’s technique.14 For the mandibular procedure we used the Hunsuck modification of the sagittal split osteotomy.15 Forty-nine iliac crest grafts were harvested; and 64 patients had additional osteotomies (genioplasty, malar osteotomy, mandibular midline split, or anterior mandibular segmental osteotomy) (Table 2). The operations were done by residents under supervision or by experienced surgeons. None of the patients donated blood preoperatively. Total intravenous anaesthesia was given with propofol (3–5 mg/kg/h) and remifentanil (0.3–0.5 g/kg/min). Controlled arterial hypotension (mean arterial pressure 55–80 mmHg, systolic arterial pressure 80–120 mmHg) was established mainly as a side effect of anaesthesia. All patients were initially given clonidine 1–2 g/kg and a bolus of prednisolone 250 mg intravenously. If necessary, small bolus doses of urapidil 0.3–2 mg/kg, were given. Tissue perfusion was optimised by giving 6% /200/0.5 hydroxyethyl starch 500 ml before segmentation of the maxilla. Haemoglobin concentration and packed cell volume (PCV) were measured the day before operation and on the first postoperative day. Intraoperative measurements were indicated by the anaesthetist. Operating time was calculated from the first incision to the last suture. The indication for transfusion was a haemoglobin concentration of less than 70 g/L or a PCV of less than 0.20, according to recent recommendations.1,8,9,16 To aid our statistical analysis we used the Statistical Package for the Social Sciences (SPSS Inc., Chicago, USA). The patients were assigned to two main groups: no additional procedures (N) and additional procedures (APs). The latter was divided into the subgroups iliac crest graft (I), additional osteotomies (AOs) and iliac crest graft with simultaneous additional osteotomies (IAOs) (Table 3). The significance of differences between the two main groups was assessed with Student’s two-tailed t test. The analysis of variance (ANOVA)
was used to assess the significance of differences between the three subgroups. The influence of sex was analysed with the two-tailed t test. The correlation coefficients between age and operating time and reduction in haemoglobin concentration and PCV were calculated. Probabilities of less than 0.05 were considered significant.
Results A total of 225 patients had bimaxillary orthognathic procedures with MMO within the three-year period. Their mean age was 26 years (range 16–54) and the male:female ratio 1:1.47. The preoperative haemoglobin concentrations varied from 100 to 175 g/L (mean (SD) 142 (126) g/L). PCV ranged from 0.28 to 0.48 preoperatively (mean (SD) 0.40 (0.32)). The mean (SD) duration of operation was 258 (57) min (range 129–389). There were no anaesthetic or surgical complications during any operation. Nine patients required two units of blood to be cross-matched, but no transfusions were given during the operation. Four patients were transfused (2%) altogether. One patient was given two units of blood. In the iliac crest group two patients were transfused with one unit, and one patient with two units of blood. The cross-match to transfusion ratio (C:T ratio) was 2.25. Postoperatively there was a mean drop in haemoglobin concentration of 25% (3–57%). The mean reduction in PCV was 26% (−3% to 58%). Operating time correlated significantly with the reductions in haemoglobin concentration (r = 0.322; p < 0.001) and PCV (r = 0.290; p < 0.001). There were no differences between men and women (haemoglobin p = 0.63; PCV p = 0.48). Age did not correlate with either haemoglobin concentration (r = −0.047; p = 0.24) or PCV (r = −0.052; p = 0.22). Patients with AP lost significantly more blood than those in the N group (p < 0.001 for haemoglobin concentration and PCV) (Table 4). There was no significant difference in blood loss between the three subgroups (AO, I, and IAO) (Table 5).
Discussion
Table 2 Additional procedures (n = 119). Type of procedure
No. of patients
Iliac crest graft Genioplasty Malar osteotomies Mandibular midline split Anterior mandibular segmental osteotomies
49 52 4 6 8
Excessive blood loss is one of the most complications of correction of craniofacial deformities. In contrast to earlier publications, autologous blood donation is not recommended any more for routine bimaxillary procedures.1–5,10–13,17,18 Most of these studies did not include MMO or give any information about segmentation.2–4,7,11,13,16–19 Moenning et al.,
278
W.B. Kretschmer et al. / British Journal of Oral and Maxillofacial Surgery 48 (2010) 276–280
Table 4 Operating time and haematological data given as mean (SD). No additional procedures compared with additional procedures. Variable
No additional procedures (n = 132)
Additional procedures (n = 93)
p value
Operating time (min) Preoperative haemoglobin (g/L) Preoperative packed cell volume Postoperative haemoglobin (g/L) Postoperative packed cell volume No. of patients given transfusions
237 (53) 143 (12) 0.40 (0.03) 110 (13) 0.31 (0.04) 0
286 (50) 141 (13) 0.40 (0.03) 102 (19) 0.29 (0.06) 4
<0.001 0.18 0.13 0.001 0.001
Two-tailed t test. Table 5 Operating time and haematological data given as mean (SD) Additional procedures (n = 93): subgroups. Variable
Additional osteotomies (n = 44)
Iliac crest graft (n = 29)
Additional osteotomies and iliac crest graft (n = 20)
Operating time (min) Preoperative haemoglobin (g/L) Preoperative packed cell volume Postoperative haemoglobin (g/L) Postoperative packed cell volume No. of patients given transfusions
280 (55) 140 (16) 0.40 (0.04) 103 (18) 0.29 (0.05) 1
291 (41) 141 (10) 0.40 (0.03) 101 (22) 0.29 (0.06) 3
295 (51) 142 (10) 0.40(0.03) 104 (14) 0. 29 (0.03) 0
There were no significant differences between operating times, haemoglobin concentrations, or packed cell volumes. The univariate ANOVA showed no significant differences for operation time, pre- and postoperative haemoglobin and haematocrit.
Yu et al., and Kretschmer et al. provided statistical analysis of different groups with segmental and non-segmental LeFort I osteotomies,1,5,10 but only Kretschmer et al. provided data about the “high risk” group with MMO and additional procedures.5 As their sample included no more than 21 patients and did not distinguish between different additional procedures, the present study seems to be justified. Measurement of the reductions in haemoglobin concentration and PCV on the first postoperative day was considered adequate for the calculation of intraoperative blood loss, whereas measurement of the weight of surgical swabs and the contents of suction bottles is thought to underestimate true blood loss.5,6,10 An assessment after one week, as reported by Ueki et al., does not correspond with the general clinical protocols.13 The exclusion of patients with haemorrhagic diatheses is standard.4,10,18 Other exclusion criteria were not reported in most studies.1–4,7,10,12,13,16,18–20 Dhariwal et al. and Samman et al. also included syndromic patients and those with cleft palate.16,17 Hypotensive anaesthesia has become a standard way to reduce blood loss during orthognathic surgery,1,6,7,10,11,13,16,17,19,20 and total intravenous anaesthesia is an established method. Propofol and remifentanil both reduce cardiac output by either negative inotropic or dromotropic effects.21 As orthognathic patients rarely present with critical medical conditions, side effects such as reduction of coronary perfusion are not of great importance. Hydroxyethyl starch was given in all cases to reduce the risk of avascular complications of maxillary segmentation. Haemostatic problems are not expected when the infusion is limited to 60 ml/kg daily.5,22 So far, the influence of sex and age on blood loss has been investigated only by Moenning et al.,1 who found significantly higher blood loss among men (p < 0.001), but no
influence of age. In contrast to their results, we found no difference between men and women. The data presented showed no correlation between age and the reduction in haemoglobin concentration and PCV. The transfusion rate (2%) was similar to the results of other studies with bimaxillary procedures including MMO. Moenning et al. transfused one patient of 67 subjects with BSSO and multi-piece maxilla (2%) and two patients of 88 with bimaxillary osteotomies and additional procedures (2%).1 Unfortunately, the latter included segmented and non-segmented LeFort I osteotomies. In a small sample of 21 bimaxillary procedures, Yu et al. had to give one patient a transfusion.10 Dhariwal et al. considered four transfusions in their study on 115 consecutive cases appropriate (3%).11 Kretschmer et al. gave one unit of blood in one case of 21 bimaxillary osteotomies with MMO and additional procedures, whereas none of the 48 patients with no additional procedures were given transfusions.5 In contrast to these publications Samman et al. reported a transfusion rate of 27% including several types of maxillary procedures, and iliac crest grafts (18%).17 Crucial factors for the excessive blood loss in their study might be the inclusion of 10 Le Fort II osteotomies and syndromic patients. Segmentation of the maxilla seems to have an important influence. The blood loss in the study of Yu et al. during segmental maxillary osteotomies was almost twice that of single-piece Le Fort I osteotomies.10 No statistical analysis was done fore these two groups. Moenning et al. found a higher mean blood loss in the group of double-jaw surgery with multi-piece maxilla (440 ml) than in the group without segmentation (361 ml).1 No significant differences were reported. The results of Moenning et al. for the first group were similar to those of Kretschmer et al.1,5 Although blood
W.B. Kretschmer et al. / British Journal of Oral and Maxillofacial Surgery 48 (2010) 276–280
loss was higher than in the other groups, no significant differences were found. The role of additional procedures is controversial. Gong et al. advocated autologous blood donation when bone is grafted simultaneously.2 The large number of transfusions in bimaxillary osteotomies with iliac crest grafts (75%) reported by Ash and Mercuri seems to be exaggerated nowadays.12 Moenning et al. and Dhariwal et al. found no significant differences in blood loss between bimaxillary osteotomies with or without additional procedures.1,11 This confirms the findings of Kretschmer et al. for the group with single-piece maxilla and AP.5 The mean reduction in haemoglobin concentration in this group was even lower (−29 g/L) than in the group without AP (−31 g/L). In their group with MMO and additional procedures blood loss was significantly higher than in the other three groups (one-piece maxilla with and without additional procedures, MMO without additional procedures). One factor for the significant drop in haemoglobin concentration and PCV in their study was the prolonged mean operating time of 1 h. The mean difference between the N and the AP group was 49 min in the present study. The strong correlation between duration of operating time and postoperative drop in PCV was confirmed by Yu et al.10 Combined with maxillary segmentation, additional procedures raised blood loss significantly in the present study (p < 0.001 for haemoglobin concentration and PCV). In the AP group four patients were given transfusions (4%), whereas no blood was given in the N group. In contrast to our expectations, we found no significant difference between the IAO group and the two groups with one additional procedure. In times of limited economic resources, over-ordering of cross-matched blood should be avoided; a C:T ratio of 2.5 is considered acceptable.11,17 The C:T ratio was 2.3 in the present study. Analysis of different groups may also help to reduce over-ordering of blood for bimaxillary osteotomies. Transfusion of patients having bimaxillary osteotomies with a single-piece maxilla is unlikely, and this has been confirmed by several recent studies.5,10,13 Although segmentation of the maxilla increases blood loss, a general recommendation for autologous blood donation cannot be given when no additional procedures are planned.1,10 We did not give transfusions to any of our 132 patients in this group. Combined with additional procedures, the incidence of homologous blood transfusion was significantly higher (4%). This percentage is clearly below the rate of 10% considered to be the threshold over which it is legally necessary to inform the patient about autologous blood donation according to the German Supreme Court.4 As new testing methods have reduced the risk of hepatitis C and HIV infection after homologous transfusion, and autologous transfusions can lead to serious transfusion reactions as a result of errors in the treatment and processing of blood, we advocate only preoperative blood typing for this “high risk” group.23,24 The use of tranexamic acid, as recently shown by Choi et al., would be an additional option to reduce blood
279
loss in bimaxillary osteotomies with MMO and additional procedures.25
References 1. Moenning JE, Bussard DA, Lapp TH, Garrison BT. Average blood loss and the risk of requiring perioperative blood transfusion in 506 orthognathic surgical procedures. J Oral Maxillofac Surg 1995;53:880–3. 2. Gong SG, Krishnan V, Waack D. Blood transfusions in bimaxillary orthognathic surgery: are they necessary? Int J Adult Orthodon Orthognath Surg 2002;17:314–7. 3. Nkenke E, Kessler P, Wiltfang J, Neukam FW, Weisbach V. Hemoglobin value reduction and necessity of transfusion in bimaxillary orthognathic surgery. J Oral Maxillofac Surg 2005;63:623–8. 4. Kessler P, Hegewald J, Adler W, et al. Is there a need for autogenous blood donation in orthognathic surgery? Plast Reconstr Surg 2006;117:571–6. 5. Kretschmer WB, Köster U, Dietz K, Zoder W, Wangerin K. Factors for intraoperative blood loss in bimaxillary osteotomies. J Oral Maxillofac Surg 2008;66:1399–403. 6. Schaberg SJ, Kelly JF, Terry BC, Posner MA, Anderson EF. Blood loss and hypotensive anesthesia in oro-facial corrective surgery. J Oral Surg 1976;34:147–56. 7. Praveen K, Narayanan V, Muthusekhar MR, Baig MF. Hypotensive anaesthesia and blood loss in orthognathic surgery: a clinical study. Br J Oral Maxillofac Surg 2001;39:138–40. 8. Regan F, Taylor C. Blood transfusion medicine. BMJ 2002;325:143–7. 9. Gibbons AJ, Dhariwal DK, Benton A, Hodder SC. Blood usage in maxillofacial surgery. Br J Oral Maxillofac Surg 2002;40:350. 10. Yu CNF, Chow TK, Kwan ASK, Wong SL, Fung SC. Intra-operative blood loss and operating time in orthognathic surgery using induced hypotensive general anesthesia: prospective study. Hong Kong Med J 2000;6:307–11. 11. Dhariwal DK, Gibbons AJ, Kittur MA, Sugar AW. Blood transfusion requirements in bimaxillary osteotomies. Br J Oral Maxillofac Surg 2004;42:231–5. 12. Ash DC, Mercuri LG. The relationship between blood ordered and blood administered in orthognathic surgery: a retrospective study. J Oral Maxillofac Surg 1985;43:944–6. 13. Ueki K, Marukawa K, Shimada M, Nakagawa K, Yamamoto E. The assessment of blood loss in orthognathic surgery for prognathia. J Oral Maxillofac Surg 2005;63:350–4. 14. Bell WH. Le Fort I osteotomy for correction of maxillary deformities. J Oral Surg 1975;33:412–26. 15. Hunsuck EE. A modified intraoral sagittal splitting technique for correction of mandibular prognathism. J Oral Surg 1968;26:250–3. 16. Rohling RG, Haers PE, Zimmermann AP, Schanz U, Marquetaud R, Sailer H. Multimodal strategy for reduction of homologous transfusions in cranio-maxillofacial surgery. Int J Oral Maxillofac Surg 1999;28:137–42. 17. Samman N, Cheung LK, Tong AC, Tideman H. Blood loss and transfusion requirements in orthognathic surgery. J Oral Maxillofac Surg 1996;54:21–4. 18. Nath A, Pogrel MA. Preoperative autologous blood donation for oral and maxillofacial surgery: an analysis of 913 patients. J Oral Maxillofac Surg 2005;63:347–9. 19. Stewart A, Newman L, Sneddon K, Harris M. Aprotinin reduces blood loss and the need for transfusion in orthognathic surgery. Br J Oral Maxillofac Surg 2001;39:365–70. 20. Zellin G, Rasmusson L, Palsson J, Kahnberg AE. Evaluation of hemorrhage depressors on blood loss during orthognathic surgery: a retrospective study. J Oral Maxillofac Surg 2004;62:662–6. 21. Stoelting RK, Hillier SC, editors. Pharmacology and physiology in anesthetic practice. 4th ed. Philadelphia: Lippincott, Williams and Wilkins; 2006.
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22. Gallandat Huet RCG, Siemons AW, Baus D, et al. A novel hydroxyethyl starch for effective perioperative plasma volume substitution in cardiac surgery. Can J Anesth 2000;47:1207–15. 23. Goodnough LT. Risks of blood transfusion. Crit Care Med 2003;31(Suppl.):678–86.
24. Vanderlinde ES, Heal JM, Blumberg N. Autologous transfusion. BMJ 2002;324:772–5. 25. Choi WS, Irwin MG, Samman N. The effect of tranexamic acid on blood loss during orthognathic surgery: a randomized controlled trial. J Oral Maxillofac Surg 2009;67:125–33.
British Journal of Oral and Maxillofacial Surgery 48 (2010) 276–280
Intraoperative blood loss in bimaxillary orthognathic surgery with multisegmental Le Fort I osteotomies and additional procedures W.B. Kretschmer a,b,∗ , G. Baciut b , Mihaela Bacuit b , W. Zoder a , K. Wangerin a a b
Department of Oral and Maxillofacial Surgery, Marienhospital, Stuttgart, Germany Clinic of Cranio-Maxillofacial Surgery, University of Medicine and Pharmacy, Cluj-Napoca, Romania
Accepted 7 July 2009 Available online 4 August 2009
Abstract Autologous blood donation is not currently recommended by most authors for routine bimaxillary osteotomies. There are few data about bimaxillary procedures with multisegmental maxillary osteotomies. Our aim was to investigate the effect of additional osteotomies and iliac crest grafts on operative blood loss. A total of 225 consecutive patients having bimaxillary multisegmental osteotomies during a three-year period (January 2006–January 2009) were examined to see if their haemoglobin concentration and packed cell volume were reduced. The influence of iliac crest grafts, additional osteotomies (genioplasty, malar osteotomy, iliac crest graft, anterior mandibular segmental osteotomy), operating time, age, and sex were assessed. Neither age nor sex influenced blood loss, whereas operating time correlated significantly with reductions in haemoglobin concentration and packed cell volume. Blood loss was significantly higher in the group who had additional procedures (p 0.001 for haemoglobin concentration and packed cell volume) than in the group who had no additional procedures, whereas there were no significant differences among the three subgroups who had additional procedures (additional osteotomies, iliac crest grafts, or both procedures). Four patients who had additional procedures required transfusion, whereas no blood was given in the group who had no additional procedures. Because the transfusion rate was so low, we could make no general recommendation for preoperative blood donation in such cases. © 2009 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved. Keywords: Blood loss; Orthognathic surgery; Bimaxillary osteotomies; Multisegmental maxillary osteotomy; Additional procedures
Introduction Autologous blood donation is not considered to be essential for bimaxillary orthognathic surgery.1–5 Hypotensive anaesthesia reduces blood loss by more than 40%.6,7 Changes in the criteria for transfusion have also reduced the previously high transfusion rates.1,8,9 However, factors such as segmentation of the maxilla, grafts from the iliac crest, or additional osteotomies raise the likelihood of transfusion significantly.1,2,5,10–12 Operating time is also correlated with ∗
Corresponding author at: Department of Oral and Maxillofacial Surgery, Marienhospital, Stuttgart, Boeheimstr. 37, 70199 Stuttgart, Germany. Tel.: +49 711 6489 8261; fax: +49 711 6489 8262. E-mail address: [email protected] (W.B. Kretschmer).
blood loss, as the studies of Kretschmer et al., Yu et al., and Ueki et al., have shown.5,10,13 Unfortunately there are few data about the “high risk” group of bimaxillary osteotomies with segmentation of the maxilla and additional procedures. We know of no study about the influence of different additional procedures on blood loss in this group. The purpose of the present study was to distinguish factors that led to a high risk of transfusion within the group of bimaxillary osteotomies with segmentation of the maxilla.
Patients and methods The data about 225 consecutive patients (134 women and 91 men aged 16–54 years) who had bimaxillary operations
0266-4356/$ – see front matter © 2009 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
doi:10.1016/j.bjoms.2009.07.011
W.B. Kretschmer et al. / British Journal of Oral and Maxillofacial Surgery 48 (2010) 276–280 Table 1 Maxillary osteotomies (n = 225).
277
Table 3 Groups and subgroups (n = 225).
Type of segmental osteotomy
No. of patients
Group/subgroup
No. of patients
Two-piece Three-piece Four-piece Five-piece
59 163 2 1
No additional procedure Additional procedures Additional osteotomies Iliac crest graft Additional osteotomies and iliac crest graft
132 93 44 29 20
with multisegmental maxillary osteotomies (MMOs) from January 2006 to January 2009 were assessed. Exclusion criteria were the presence of coagulopathy, cleft palate, or craniofacial syndromes. All patients were healthy (American Society of Anesthesiologists grade I). The MMO (Table 1) was done using Bell’s technique.14 For the mandibular procedure we used the Hunsuck modification of the sagittal split osteotomy.15 Forty-nine iliac crest grafts were harvested; and 64 patients had additional osteotomies (genioplasty, malar osteotomy, mandibular midline split, or anterior mandibular segmental osteotomy) (Table 2). The operations were done by residents under supervision or by experienced surgeons. None of the patients donated blood preoperatively. Total intravenous anaesthesia was given with propofol (3–5 mg/kg/h) and remifentanil (0.3–0.5 g/kg/min). Controlled arterial hypotension (mean arterial pressure 55–80 mmHg, systolic arterial pressure 80–120 mmHg) was established mainly as a side effect of anaesthesia. All patients were initially given clonidine 1–2 g/kg and a bolus of prednisolone 250 mg intravenously. If necessary, small bolus doses of urapidil 0.3–2 mg/kg, were given. Tissue perfusion was optimised by giving 6% /200/0.5 hydroxyethyl starch 500 ml before segmentation of the maxilla. Haemoglobin concentration and packed cell volume (PCV) were measured the day before operation and on the first postoperative day. Intraoperative measurements were indicated by the anaesthetist. Operating time was calculated from the first incision to the last suture. The indication for transfusion was a haemoglobin concentration of less than 70 g/L or a PCV of less than 0.20, according to recent recommendations.1,8,9,16 To aid our statistical analysis we used the Statistical Package for the Social Sciences (SPSS Inc., Chicago, USA). The patients were assigned to two main groups: no additional procedures (N) and additional procedures (APs). The latter was divided into the subgroups iliac crest graft (I), additional osteotomies (AOs) and iliac crest graft with simultaneous additional osteotomies (IAOs) (Table 3). The significance of differences between the two main groups was assessed with Student’s two-tailed t test. The analysis of variance (ANOVA)
was used to assess the significance of differences between the three subgroups. The influence of sex was analysed with the two-tailed t test. The correlation coefficients between age and operating time and reduction in haemoglobin concentration and PCV were calculated. Probabilities of less than 0.05 were considered significant.
Results A total of 225 patients had bimaxillary orthognathic procedures with MMO within the three-year period. Their mean age was 26 years (range 16–54) and the male:female ratio 1:1.47. The preoperative haemoglobin concentrations varied from 100 to 175 g/L (mean (SD) 142 (126) g/L). PCV ranged from 0.28 to 0.48 preoperatively (mean (SD) 0.40 (0.32)). The mean (SD) duration of operation was 258 (57) min (range 129–389). There were no anaesthetic or surgical complications during any operation. Nine patients required two units of blood to be cross-matched, but no transfusions were given during the operation. Four patients were transfused (2%) altogether. One patient was given two units of blood. In the iliac crest group two patients were transfused with one unit, and one patient with two units of blood. The cross-match to transfusion ratio (C:T ratio) was 2.25. Postoperatively there was a mean drop in haemoglobin concentration of 25% (3–57%). The mean reduction in PCV was 26% (−3% to 58%). Operating time correlated significantly with the reductions in haemoglobin concentration (r = 0.322; p < 0.001) and PCV (r = 0.290; p < 0.001). There were no differences between men and women (haemoglobin p = 0.63; PCV p = 0.48). Age did not correlate with either haemoglobin concentration (r = −0.047; p = 0.24) or PCV (r = −0.052; p = 0.22). Patients with AP lost significantly more blood than those in the N group (p < 0.001 for haemoglobin concentration and PCV) (Table 4). There was no significant difference in blood loss between the three subgroups (AO, I, and IAO) (Table 5).
Discussion
Table 2 Additional procedures (n = 119). Type of procedure
No. of patients
Iliac crest graft Genioplasty Malar osteotomies Mandibular midline split Anterior mandibular segmental osteotomies
49 52 4 6 8
Excessive blood loss is one of the most complications of correction of craniofacial deformities. In contrast to earlier publications, autologous blood donation is not recommended any more for routine bimaxillary procedures.1–5,10–13,17,18 Most of these studies did not include MMO or give any information about segmentation.2–4,7,11,13,16–19 Moenning et al.,
278
W.B. Kretschmer et al. / British Journal of Oral and Maxillofacial Surgery 48 (2010) 276–280
Table 4 Operating time and haematological data given as mean (SD). No additional procedures compared with additional procedures. Variable
No additional procedures (n = 132)
Additional procedures (n = 93)
p value
Operating time (min) Preoperative haemoglobin (g/L) Preoperative packed cell volume Postoperative haemoglobin (g/L) Postoperative packed cell volume No. of patients given transfusions
237 (53) 143 (12) 0.40 (0.03) 110 (13) 0.31 (0.04) 0
286 (50) 141 (13) 0.40 (0.03) 102 (19) 0.29 (0.06) 4
<0.001 0.18 0.13 0.001 0.001
Two-tailed t test. Table 5 Operating time and haematological data given as mean (SD) Additional procedures (n = 93): subgroups. Variable
Additional osteotomies (n = 44)
Iliac crest graft (n = 29)
Additional osteotomies and iliac crest graft (n = 20)
Operating time (min) Preoperative haemoglobin (g/L) Preoperative packed cell volume Postoperative haemoglobin (g/L) Postoperative packed cell volume No. of patients given transfusions
280 (55) 140 (16) 0.40 (0.04) 103 (18) 0.29 (0.05) 1
291 (41) 141 (10) 0.40 (0.03) 101 (22) 0.29 (0.06) 3
295 (51) 142 (10) 0.40(0.03) 104 (14) 0. 29 (0.03) 0
There were no significant differences between operating times, haemoglobin concentrations, or packed cell volumes. The univariate ANOVA showed no significant differences for operation time, pre- and postoperative haemoglobin and haematocrit.
Yu et al., and Kretschmer et al. provided statistical analysis of different groups with segmental and non-segmental LeFort I osteotomies,1,5,10 but only Kretschmer et al. provided data about the “high risk” group with MMO and additional procedures.5 As their sample included no more than 21 patients and did not distinguish between different additional procedures, the present study seems to be justified. Measurement of the reductions in haemoglobin concentration and PCV on the first postoperative day was considered adequate for the calculation of intraoperative blood loss, whereas measurement of the weight of surgical swabs and the contents of suction bottles is thought to underestimate true blood loss.5,6,10 An assessment after one week, as reported by Ueki et al., does not correspond with the general clinical protocols.13 The exclusion of patients with haemorrhagic diatheses is standard.4,10,18 Other exclusion criteria were not reported in most studies.1–4,7,10,12,13,16,18–20 Dhariwal et al. and Samman et al. also included syndromic patients and those with cleft palate.16,17 Hypotensive anaesthesia has become a standard way to reduce blood loss during orthognathic surgery,1,6,7,10,11,13,16,17,19,20 and total intravenous anaesthesia is an established method. Propofol and remifentanil both reduce cardiac output by either negative inotropic or dromotropic effects.21 As orthognathic patients rarely present with critical medical conditions, side effects such as reduction of coronary perfusion are not of great importance. Hydroxyethyl starch was given in all cases to reduce the risk of avascular complications of maxillary segmentation. Haemostatic problems are not expected when the infusion is limited to 60 ml/kg daily.5,22 So far, the influence of sex and age on blood loss has been investigated only by Moenning et al.,1 who found significantly higher blood loss among men (p < 0.001), but no
influence of age. In contrast to their results, we found no difference between men and women. The data presented showed no correlation between age and the reduction in haemoglobin concentration and PCV. The transfusion rate (2%) was similar to the results of other studies with bimaxillary procedures including MMO. Moenning et al. transfused one patient of 67 subjects with BSSO and multi-piece maxilla (2%) and two patients of 88 with bimaxillary osteotomies and additional procedures (2%).1 Unfortunately, the latter included segmented and non-segmented LeFort I osteotomies. In a small sample of 21 bimaxillary procedures, Yu et al. had to give one patient a transfusion.10 Dhariwal et al. considered four transfusions in their study on 115 consecutive cases appropriate (3%).11 Kretschmer et al. gave one unit of blood in one case of 21 bimaxillary osteotomies with MMO and additional procedures, whereas none of the 48 patients with no additional procedures were given transfusions.5 In contrast to these publications Samman et al. reported a transfusion rate of 27% including several types of maxillary procedures, and iliac crest grafts (18%).17 Crucial factors for the excessive blood loss in their study might be the inclusion of 10 Le Fort II osteotomies and syndromic patients. Segmentation of the maxilla seems to have an important influence. The blood loss in the study of Yu et al. during segmental maxillary osteotomies was almost twice that of single-piece Le Fort I osteotomies.10 No statistical analysis was done fore these two groups. Moenning et al. found a higher mean blood loss in the group of double-jaw surgery with multi-piece maxilla (440 ml) than in the group without segmentation (361 ml).1 No significant differences were reported. The results of Moenning et al. for the first group were similar to those of Kretschmer et al.1,5 Although blood
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loss was higher than in the other groups, no significant differences were found. The role of additional procedures is controversial. Gong et al. advocated autologous blood donation when bone is grafted simultaneously.2 The large number of transfusions in bimaxillary osteotomies with iliac crest grafts (75%) reported by Ash and Mercuri seems to be exaggerated nowadays.12 Moenning et al. and Dhariwal et al. found no significant differences in blood loss between bimaxillary osteotomies with or without additional procedures.1,11 This confirms the findings of Kretschmer et al. for the group with single-piece maxilla and AP.5 The mean reduction in haemoglobin concentration in this group was even lower (−29 g/L) than in the group without AP (−31 g/L). In their group with MMO and additional procedures blood loss was significantly higher than in the other three groups (one-piece maxilla with and without additional procedures, MMO without additional procedures). One factor for the significant drop in haemoglobin concentration and PCV in their study was the prolonged mean operating time of 1 h. The mean difference between the N and the AP group was 49 min in the present study. The strong correlation between duration of operating time and postoperative drop in PCV was confirmed by Yu et al.10 Combined with maxillary segmentation, additional procedures raised blood loss significantly in the present study (p < 0.001 for haemoglobin concentration and PCV). In the AP group four patients were given transfusions (4%), whereas no blood was given in the N group. In contrast to our expectations, we found no significant difference between the IAO group and the two groups with one additional procedure. In times of limited economic resources, over-ordering of cross-matched blood should be avoided; a C:T ratio of 2.5 is considered acceptable.11,17 The C:T ratio was 2.3 in the present study. Analysis of different groups may also help to reduce over-ordering of blood for bimaxillary osteotomies. Transfusion of patients having bimaxillary osteotomies with a single-piece maxilla is unlikely, and this has been confirmed by several recent studies.5,10,13 Although segmentation of the maxilla increases blood loss, a general recommendation for autologous blood donation cannot be given when no additional procedures are planned.1,10 We did not give transfusions to any of our 132 patients in this group. Combined with additional procedures, the incidence of homologous blood transfusion was significantly higher (4%). This percentage is clearly below the rate of 10% considered to be the threshold over which it is legally necessary to inform the patient about autologous blood donation according to the German Supreme Court.4 As new testing methods have reduced the risk of hepatitis C and HIV infection after homologous transfusion, and autologous transfusions can lead to serious transfusion reactions as a result of errors in the treatment and processing of blood, we advocate only preoperative blood typing for this “high risk” group.23,24 The use of tranexamic acid, as recently shown by Choi et al., would be an additional option to reduce blood
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loss in bimaxillary osteotomies with MMO and additional procedures.25
References 1. Moenning JE, Bussard DA, Lapp TH, Garrison BT. Average blood loss and the risk of requiring perioperative blood transfusion in 506 orthognathic surgical procedures. J Oral Maxillofac Surg 1995;53:880–3. 2. Gong SG, Krishnan V, Waack D. Blood transfusions in bimaxillary orthognathic surgery: are they necessary? Int J Adult Orthodon Orthognath Surg 2002;17:314–7. 3. Nkenke E, Kessler P, Wiltfang J, Neukam FW, Weisbach V. Hemoglobin value reduction and necessity of transfusion in bimaxillary orthognathic surgery. J Oral Maxillofac Surg 2005;63:623–8. 4. Kessler P, Hegewald J, Adler W, et al. Is there a need for autogenous blood donation in orthognathic surgery? Plast Reconstr Surg 2006;117:571–6. 5. Kretschmer WB, Köster U, Dietz K, Zoder W, Wangerin K. Factors for intraoperative blood loss in bimaxillary osteotomies. J Oral Maxillofac Surg 2008;66:1399–403. 6. Schaberg SJ, Kelly JF, Terry BC, Posner MA, Anderson EF. Blood loss and hypotensive anesthesia in oro-facial corrective surgery. J Oral Surg 1976;34:147–56. 7. Praveen K, Narayanan V, Muthusekhar MR, Baig MF. Hypotensive anaesthesia and blood loss in orthognathic surgery: a clinical study. Br J Oral Maxillofac Surg 2001;39:138–40. 8. Regan F, Taylor C. Blood transfusion medicine. BMJ 2002;325:143–7. 9. Gibbons AJ, Dhariwal DK, Benton A, Hodder SC. Blood usage in maxillofacial surgery. Br J Oral Maxillofac Surg 2002;40:350. 10. Yu CNF, Chow TK, Kwan ASK, Wong SL, Fung SC. Intra-operative blood loss and operating time in orthognathic surgery using induced hypotensive general anesthesia: prospective study. Hong Kong Med J 2000;6:307–11. 11. Dhariwal DK, Gibbons AJ, Kittur MA, Sugar AW. Blood transfusion requirements in bimaxillary osteotomies. Br J Oral Maxillofac Surg 2004;42:231–5. 12. Ash DC, Mercuri LG. The relationship between blood ordered and blood administered in orthognathic surgery: a retrospective study. J Oral Maxillofac Surg 1985;43:944–6. 13. Ueki K, Marukawa K, Shimada M, Nakagawa K, Yamamoto E. The assessment of blood loss in orthognathic surgery for prognathia. J Oral Maxillofac Surg 2005;63:350–4. 14. Bell WH. Le Fort I osteotomy for correction of maxillary deformities. J Oral Surg 1975;33:412–26. 15. Hunsuck EE. A modified intraoral sagittal splitting technique for correction of mandibular prognathism. J Oral Surg 1968;26:250–3. 16. Rohling RG, Haers PE, Zimmermann AP, Schanz U, Marquetaud R, Sailer H. Multimodal strategy for reduction of homologous transfusions in cranio-maxillofacial surgery. Int J Oral Maxillofac Surg 1999;28:137–42. 17. Samman N, Cheung LK, Tong AC, Tideman H. Blood loss and transfusion requirements in orthognathic surgery. J Oral Maxillofac Surg 1996;54:21–4. 18. Nath A, Pogrel MA. Preoperative autologous blood donation for oral and maxillofacial surgery: an analysis of 913 patients. J Oral Maxillofac Surg 2005;63:347–9. 19. Stewart A, Newman L, Sneddon K, Harris M. Aprotinin reduces blood loss and the need for transfusion in orthognathic surgery. Br J Oral Maxillofac Surg 2001;39:365–70. 20. Zellin G, Rasmusson L, Palsson J, Kahnberg AE. Evaluation of hemorrhage depressors on blood loss during orthognathic surgery: a retrospective study. J Oral Maxillofac Surg 2004;62:662–6. 21. Stoelting RK, Hillier SC, editors. Pharmacology and physiology in anesthetic practice. 4th ed. Philadelphia: Lippincott, Williams and Wilkins; 2006.
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22. Gallandat Huet RCG, Siemons AW, Baus D, et al. A novel hydroxyethyl starch for effective perioperative plasma volume substitution in cardiac surgery. Can J Anesth 2000;47:1207–15. 23. Goodnough LT. Risks of blood transfusion. Crit Care Med 2003;31(Suppl.):678–86.
24. Vanderlinde ES, Heal JM, Blumberg N. Autologous transfusion. BMJ 2002;324:772–5. 25. Choi WS, Irwin MG, Samman N. The effect of tranexamic acid on blood loss during orthognathic surgery: a randomized controlled trial. J Oral Maxillofac Surg 2009;67:125–33.