/home/opencode/cpanel/stomaeduj_hacked/uploads/2018/01/Article_5_v5_1.pdf MAXILLOFACIAL SURGERY BLOODLOSS AND TRANSFUSION NEED IN ORTHOGNATHIC SURGERY: Review Article REVIEW OF LITERATURE Constantinus Politis1a*, Jimoh Olubanwo Agbaje1b, Ivo Lambrichts2c 1 OMFS-IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, Katholieke Universiteit Leuven, Leuven, Belgium and Depart- ment of Oral and Maxillofacial Surgery, University Hospitals Leuven, BE-3000 Leuven, Belgium 2 Faculty of Medicine, Hasselt University, Diepenbeek, Belgium; Biomedical Research Institute, Laboratory of Morphology, Hasselt University, Campus Diepenbeek, BE-3590 Diepenbeek, Belgium a MD, DDS, MHA, MM, PhD, Professor b BDS, DMD, FMCDS, MMI, PhD c DDS, PhD, Professor ABSTRACT DOI: 10.25241/stomaeduj.2018.5(1).art.5 Background: Blood loss during orthognathic surgery has gained renewed interest due to OPEN ACCESS This is an Open Access article under the CC the omission of surgical final splints in bimaxillary surgery, which increased operative time, BY-NC 4.0 license. while orthognathic surgery is increasingly indicated for the treatment of the obstructive sleep Peer-Reviewed Article apnea syndrome (OSAS). OSAS subjects are usually older with more medical comorbidity Citation: Politis C, Agbaje JO, which requires blood transfusion. Lambrichts I. Bloodloss and transfusion Objective: To review (reported) blood loss and transfusion practice in orthognathic surgery need in orthognathic surgery: review of literature. Stoma Edu J. 2018;5(1):44-51. in the literature published between 1976 and 2012 and to compare these data with more Academic Editor: Heinz Kniha, DDS, recent developments. The relationship between the duration of the surgery and the related MD, PhD, Associate Professor, Ludwig- blood loss and/or transfusion was examined. Maximilians- München University, München, Germany Data Sources: The 1976-2012 orthognathic literature was searched to determine the relationship between the duration of the surgery and the related blood loss and/or Received: January 03, 2018 Revised: February 05, 2018 transfusion. Acccepted: February 23, 2018 Study Selection: Articles containing clear information on the operation time, blood loss, Published: February 26, 2018 transfusion, and orthognathic surgery were included. *Corresponding author: Professor Data Extraction: Information on the operation time, blood loss, transfusion, and Constantinus Politis, MD, DDS, MHA, MM, PhD, Department of Oral & Maxil- orthognathic surgery was extracted. lofacial Surgery, University Hospitals of Leuven, Kapucijnenvoer 33, 3000 Data Synthesis: Different descriptions of procedures and techniques are grouped together Leuven, Belgium, Telephone: +32 (0) in a concise and coherent way, resulting in a number of categories per label. Using this 16.341780, Fax: +32 (0) 16 3 32437, e-mail: c.politis@village.uunet.be grouping various targeted questions are exploited and answered. Keywords: orthognathic surgery, blood loss, operation time, blood transfusion. Copyright: © 2018 the Editorial Coun- cil for the Stomatology Edu Journal. 1. Introduction Although a Cochrane review recommends adherence Blood loss during orthognathic surgery has gained to a restrictive transfusion strategy (7 to 8 g/dL) [4] in renewed interest for several reasons. A first reason is hospitalized stable patients, a remarkable tendency to found in a recent school of thought that advocates the preoperative autologous blood donation is seen even omission of surgical final splints in bimaxillary surgery but in surgical procedures – such as single-jaw SSO – that insists on the perioperative achievement of an excellent nowadays are considered low risk for blood loss [5]. interdigitation, which in many cases can be achieved The aim of the present contribution is to review (reported) only by multisegmenting the Le Fort I osteotomy at the blood loss and transfusion practice in orthognathic surgery cost of increased operative time. Because orthognathic in the literature published between 1976 and 2012. The surgery is increasingly used to enhance facial aesthetics, relationship between the duration of the surgery and the many concomitant procedures have been reported [1], related blood loss and/or transfusion was examined. all of them influencing the duration of the operative procedure and blood loss. Orthognathic patients used to be generally young adults without major comorbidities. 2. Methods That scope is changing because orthognathic surgery 2.1. Research questions is increasingly indicated for the treatment of the The relevant clinical questions that should be answered obstructive sleep apnea syndrome (OSAS). OSAS are as follows: subjects undergoing maxillomandibular advancement • Is the operation time a predictor for blood loss and/ surgery are likely older with more medical comorbidity or blood transfusion? [2], influencing the limit below which blood transfusion • Are concomitant procedures (segmentation, is indicated. Blood loss during surgery requiring genioplasty, rhinoplasty, iliac crest grafts) predictors blood transfusion is viewed as an important operative for blood loss and/or blood transfusion? complication, designated as a grade II complication in • Is the practice of preoperative autologous blood the Clavien-Dindo complication classification system, donation a predictor for blood loss and/or blood which is becoming widely accepted for surgical transfusion? complications, even in oral and maxillofacial surgery [3]. • What are the measures taken to minimise blood 44 Stoma Edu J. 2018;5(1): 44-51 http://www.stomaeduj.com BLOODLOSS AND TRANSFUSION NEED IN ORTHOGNATHIC SURGERY: REVIEW OF LITERATURE loss during orthognathic surgery? Review Article Table 1. Summary of the entries that were introduced in PubMed, • Is operating time correlated to blood loss and/or Scopus and LIMO. blood transfusion? Entry Medline Scopus Limo • Is blood loss related to blood transfusion? • Is an evolution in time detectable concerning Blood loss and 121 6 80 duration of operations and/or blood loss? orthognathic • The methodological questions that need to be Transfusion and 62 6 26 answered are as follows: orthognathic • How is blood loss defined or measured? Operative time and 35 10 157 orthognathic • How is operation time defined? Hypotension and • How is hypotension/normotension defined? 50 5 18 orthognathic • How is mean arterial pressure (MAP) measured and Blood transfusion and reported? orthognathic surgery 62 2 25 2.2. Literature review: selection criteria procedures were often not suitable for inclusion because Table 1 summarizes the entries that were introduced in they did not separate the different categories needed. No PubMed, Scopus and LIMO. minimal number of patients was required to be included. No limits were set for language, year, field. A manual search for articles containing information on the operation time, blood loss, transfusion, and orthognathic surgery was 3. Results performed in the following journals until 1976: 3.1. Search results • British Journal of Oral and Maxillofacial Surgery In total, 51 papers and 2 theses were retained that • International Journal of Oral and Maxillofacial Surgery contained valuable subgroups with information. Both • Journal of Craniofacial Surgery retrospective and prospective studies were accepted, • Journal of Cranio-Maxillo-Facial Surgery no matter if the procedures were done in normotension, • Journal of Oral and Maxillofacial Surgery mild hypotension, controlled hypotension, or any other • Oral & Maxillofacial Surgery Clinics of North America tension reported (see Appendix 1) • Oral and Maxillofacial Surgery • Oral Surgery, Oral Medicine, Oral Pathology, Oral 3.2. Meta-analysis or systematic review Radiology, and Endodontics Meta-analysis was not the approach used because there • Plastic and Reconstructive Surgery was no control group for comparison. Control groups • Revue de Stomatologie et de Chirurgie Maxillo-faciale were used to compare the effect of different medications An additional manual search was done to retrieve theses that influence the depth of controlled hypotension or to on the subject of blood transfusion in orthognathic compare the effect of certain antifibrinolytic agents such surgery. Two theses were included [6,7], both in German. as aprotinin, aminocaproic acid, and tranexamic acid to stabilise clot formation. Because the levels of reduced 2.2.1. Inclusion criteria blood loss of these measures are considered below clinical The criterion for retention for further processing was a relevance compared to the type of surgical procedure clear allocation of the operation time AND/OR blood selected [8], aggregation of data is needed. Therefore, the loss AND/OR transfusion to one of following operations: following differences have been neglected: 1. SSO (advancement or set-back) • different methods to realise anaesthesia (gas, iv 2. Le Fort I osteotomy one-piece without medication); concomitant procedures • different methods to reach mild, moderate, or deep 3. Le Fort I osteotomy multisegmental or with hypotension; and additional operations • different or no use of antifibrinolytic agents. 4. Bimaxillary surgery without concomitant procedures 5. Bimaxillary surgery with simultaneous other 3.2.1. Aggregation of data procedures (e.g., iliac bone graft, cranial bone graft, Many different descriptions of procedures and genioplasty, liposuction, septoplasty, rhinoplasty techniques needed to be united in a concise and inferior turbinate reduction, and removal of third coherent way, leading to a number of categories per molars). label, allowing focus on the targeted questions. These These operations needed to be the predominant operation characteristics were defined as seen in Appendix 2. if a certain group was correlated with the duration of the operation and/or blood loss. If the predominancy of any 3.3. Measurement of blood loss of these types of operations could not be established, the To compare blood loss in comparable surgical procedures group was discarded for further analysis. (BSSO, Le Fort I, bimaxillary surgery), measurement of blood loss has to be comparable. In that respect, we found 2.2.2. Exclusion criteria that in 22 out of 51 papers, the method of measuring Exclusion criteria were craniofacial surgery in children; estimated blood loss was missing [9-30]. articles where blood loss, operation time, or transfusion In 18 out of 51 papers, the estimated blood loss was could not be clearly attributed to one of the categories measured by deducting the volume of saline used from mentioned; case reports on syndromes; and case reports the total volume in the suction unit and by weighing or reviews on major postoperative hemorrhagic events. the sponges [31-48], others 10 mL [43]. In addition, retrospective reports on large numbers of In 6 out of 51 papers, losses in sponges were not included Stomatology Edu Journal 45 BLOODLOSS AND TRANSFUSION NEED IN ORTHOGNATHIC SURGERY: REVIEW OF LITERATURE in the estimated blood loss, but the irrigation fluid and Review Article Table 2. Summary of the entries that were introduced in PubMed, the fluid collected in suction devices was [8,49-53]. Scopus and LIMO. In 5 papers/theses, the calculation was based on Study Estimate Standard Error a comparison of preoperative and postoperative hematocrit level [6,42,54,55] or blood volume [56]. Golia et al [15] -0.37310 0.3161034 The problem with estimation of preoperative and Kasahara et al [17] 3.65315 0.7732564 postoperative hemoglobin and/or hematocrit is that the timing between the preoperative and postoperative Landes et al [20] 1.46156 0.6044895 measurements differed between studies. It varied Zelllin et al [48] 4.43946 1.1349279 between 6 hours postoperatively [38] and 1 week postoperatively [46]. Ueki et al [46], however, did include the perioperative blood loss estimation. Hemodilution Table 3. Relation bloodloss versus duration of surgery. may be a problem when measuring the postoperative Evaluation between-study hemoglobin level, and the rise in hemoglobin level will Random Effects Analysis heterogeneity differ according to individual body size. I2 Q Df P-value Estimate SE p-value The postoperative blood loss was not estimated, and the 92.210 38.510 3 <.0001 2.151 1.124 0.056 blood lost in drapes and gowns was not measured. The blood lost postoperatively in drains or swallowed by the I = percentage of variation in study estimates due to heterogeneity; Q = Cochrans Q 2 statistic. If Q is smaller than the number of degrees of freedom, then the estimated patient all contribute to the ultimate blood loss that may heterogeneity equals zero (I2 = 0%); Df = Degrees of Freedom for heterogeneity test; affect the decision for blood transfusion. Also, blood lost Random Effects Analysis: DerSimonian and Laird method; SE = standard error in sinuses or tissue spaces was not accounted for [44]. blood loss and operation time, but this correlation The intraoperative blood loss estimation is always less was weak for 82 bimaxillary procedures: Spearman than the calculated blood loss [6], but the estimation correlation coefficient r = 0.325. Chen et al [31] found accuracy worsens with the amount of blood lost. Böttger a weak Spearman rank correlation between operation calculated a linear regression where the estimated blood time and blood loss in 30 mandibular surgery patients loss=0.4115 × Calculated blood loss + 406.8. In this (IVRO set-back and genioplasty). Rummasak et al [43], in calculation, a 1000 mL estimated blood loss appears a retrospective review of 208 patients with bimaxillary to correlate with 1462 mL calculated blood loss, and a orthognathic surgery, reported the following correlation 2000 mL estimated blood loss appeared to correlate between blood loss and operative time: blood loss = (2.64 with 4250 mL calculated blood loss [6]. The deviation * operative time) + 82.35. They reported a “significant” between estimation and calculation increases as the relationship because the p value was < 0.001 for R2 = volume increases. The underestimation between the 0.15. However, we should be cautious: R2 = 0.15 signifies estimated blood loss and the calculated blood loss also R = 0.387; when attempting to predict one measure from was observed by Schaberg et al [45] in a radioisotope another, coefficients below 0.40 do not yield a guess study of red blood cells. even 10% better than chance [57]. Further, the chart seems to include all data points, indicating that the whole 3.4. Measurement of duration of surgery population rather than a sample was reported. As a result, To know the duration of surgery, all papers that define p value reporting would not make sense. and measure the duration of surgery in the same manner A confusing presentation of blood loss versus operative are valid candidates to be included if the duration can be time is found in Ueki et al [46]. In regression analysis, y is clearly attributed to a specified orthognathic procedure. what we want to predict or to understand and is sometimes The operation time is defined as ‘missing’ if the starting called the dependent variable. X is called the independent point of the measurement and the endpoint of the variable or a predictor. In the equation, we want to predict measurement were not defined. In contrast to ‘age’, blood loss on the basis of operative time. So, operative time ‘weight’, and ‘length’, operation time allows variable needs to be on the x-axis, as most authors have placed interpretations. it [22,29,31,43,55,58]. Because blood loss is a continuous Out of the 51 papers retained for data acquisition, 44 variable, linear regression was used [59]. did not mention at all how the duration of surgery was Four papers [15,17,20,48] provide data of overall 163 measured; 2 stated that the duration was recorded or individual patients concerning the peroperative bloodloss documented; 2 clearly stated that the operating time and the duration of surgery (Table 2). was calculated from the first incision to the last suture Based on these studies it was possible to estimate the [42,55]; one counted from the beginning of the BSSO amount of bloodloss for every minute of surgery: per incisions to the last suture [29], and one started from minute of operation time the estimated bloodloss is 2.151 the injection of the local anesthetic to the last suture mL (= SE 1.124 mL; p = 0.056) (Table 3). [47]. Clearly, no uniform definition of operation time Several articles [6,22,29,31,43,46,58] do find a linear exists. Using operation time as a predictive variable, in correlation between blood loss and the duration of the absence of the knowledge about which two points surgery but these data could not be integrated due to were used to measure it, creates an important bias when the lack of necessary information. Besides the linear comparing studies. regression coefficient, both the standard error of the alfa- and beta-coefficient should be known as well as the total 3.5. Duration of surgery and blood loss number of patients. One would assume that the longer the operation lasts, the more blood is lost. In bimaxillary surgery, Böttger [6] 3.6. Hypotension indeed found a linear correlation between calculated There is no accepted single definition for intraoperative 46 Stoma Edu J. 2018;5(1): 44-51 http://www.stomaeduj.com BLOODLOSS AND TRANSFUSION NEED IN ORTHOGNATHIC SURGERY: REVIEW OF LITERATURE hypotension. Bijker et al [60] in a literature review found - Anesthesiologist: Review Article more than 50 different definitions of intraoperative • normovolemic hemodilution hypotension used in the recent anaesthesia literature. • application of Cell Saver Systems When it comes to controlled hypotension in the • carefully controlled body temperature orthognathic literature, again no consensus is found as • use of tranexamic acid (antifibrinolytic agent) as a to what constitutes controlled hypotension and how clot stabiliser it would differ from intraoperative hypotension. Bijker • use of aprotinin (serine protease inhibitor) et al [61] found that patient and surgical characteristics, • use of desmopressin, increasing coagulant activity notably age and duration of surgery and duration of • hypotensive anesthetic techniques low blood pressure, influence the relationship between • optimised tissue perfusion by administration of intraoperative hypotension and adverse outcome. 500 mL of hydroxyethyl starch 6%/200/0.5 before Controlled hypotension is an anesthesiological technique segmentation of the maxilla [55] to lower the mean arterial blood pressure of the patient • atraumatic nasal intubation with heated nasal tubes in orthognathic surgery on the presumption that a lower • avoidance of trauma at adenoid fossa during blood pressure correlates with less blood loss and a intubation better quality of the operation field. In the orthognathic • preoperative injection of human recombinant literature, hypotension has not been related to adverse erythropoietin (not routine in OMFS) effects except for patients with pre-existing hypofunction. • preoperative exclusion of bleeding disorders In these cases, cerebral damage or neurological deficit, • maintaining hypocapnia stroke, dysrhythmia, cardiac arrest, or even death have been reported [32]. - Surgeon: The absence of a common definition of hypotension, the • avoiding perioperative vascular injury different ways of measurement of arterial pressure, the • bipolar electrocoagulation; cutting diathermy different attitudes towards the intraoperative duration of • use of an electrocautery unit to make incisions hypotension, the timing to reverse hypotensive anaesthesia • skilled surgeons to perform the operation instead to discover and address undetected arterial hemorrhage of residents [29], and the different means to achieve hypotension render • surgical vigilance comparisons between study groups difficult. An entire • administration of local anaesthesia with range encompassing aggressive attitudes (MAP 50–55 mm vasoconstrictor immediately after intubation Hg), cautious attitudes (blood pressure 20%– 30% below • timely administration of local anaesthesia in Le Fort I mean preoperative level), and no deliberate hypotension is • fluid injection with vasoconstrictor subperiosteally reported with orthognathic surgery. at nasal floor Measurement of mean arterial pressure was mostly done • cocainisation of the nasal mucosa prior to maxillary with the aid of measurements from a radial artery catheter. surgery [45] calculated mean arterial pressure with the formula: • vasoconstriction of intranasal lining with cottonoid systolic pressure × 2/5 + diastolic pressure × 3/5. No other sponges soaked in nasal decongestant mean arterial pressure measurement formula was found • placement of the patient in a reverseTrendelenburg in the 50 other retained articles. Contemporary monitors position measuring mean arterial pressure use the following • incisions that are cleanly made through the periosteum formula: (diastolic pressure × 2) + systolic pressure) / 3. • packing of open surgical sites with gauze • local hemostatics like oxidised regenerated 3.6.1. Advantages of controlled hypotension cellulose (Surgicel®, Ethicon Inc, Johnson&Johnson Controlled hypotension has advocates and opponents. Company, Somerville, NJ, USA) Arguments raised in favour of controlled hypotension • piezosurgical osteotome are a shorter operation time, a better quality of the • endoscopic assistance for a controlled dissection operation field, diminished blood loss, and lower of nasal mucosa [62] blood transfusion. Others question the advantages • hemostats and hemoclips of controlled hypotension [6]. Choi and Samman [32] • short duration of operation studied that controversy with a systematic review and • instrumentation that allows suction with built-in concluded in support of hypotensive anaesthesia, with light system three studies reporting a significant decrease of blood • avoiding venous obstruction loss in patients receiving hypotensive anaesthesia, two studies reporting a significant decrease in transfusion 3.7. Excessive blood loss rate, and two other studies demonstrating an improved Reports concerning the need for blood transfusion also surgical field and significant reduction in operation time. give some insight into the occurrence of excessive blood Their conclusion was that hypotensive anaesthesia is loss, either directly by explicit mention or by observation most valuable in operations of long duration when of the range of blood loss. Kok-Leng Yeow and Por a large amount of blood loss and consequent blood [19] report 3 excessive bleedings in 102 orthognathic transfusion are to be expected. patients, occurring from the facial artery, maxillary artery, and pterygoid plexus separately in three patients. When 3.6.2. Minimizing perioperative bleeding we observe the reported ranges of the subgroups, we Both surgeon and anesthesiologist have means at see an upper limit of the range at 3000 mL and one upper their disposal to affect coagulation, blood loss, and the limit of 6000 mL of perioperative blood loss. Martini et al quality of the surgical field. [22], in a graph depicting the linear correlation between Stomatology Edu Journal 47 BLOODLOSS AND TRANSFUSION NEED IN ORTHOGNATHIC SURGERY: REVIEW OF LITERATURE blood loss and operation time, show two outliers of [22,37]. In case strict criteria are used to ‘trigger’ blood Review Article blood loss, one close to 2900 mL and one at 5000 mL, transfusion, the availability of autologous blood did not in an orthognathic surgery group containing 27 Le Fort seem to increase the rate of blood transfusion [25]. I operations and 52 bimaxillary cases. Choi et al [58], in a reported graph with the relationship between total blood loss and operation time in 61 patients, show 4 4. Preoperative donation of autologous blood cases of blood loss in excess of 3000 mL. The mean Preoperative autologous blood donation has several blood loss in 11 patients who received blood transfusion disadvantages. It is not risk free, and human error and the included one group of 7 patients (2,291±831.7 mL) and administration of the wrong unit of blood still can occur. one group of 4 patients (1,732±856.8 mL). Rummasak It leads to anemia and hypovolemia [6] and is more et al [43] reported retrospectively on 208 bimaxillary expensive than homologous blood donation. Patients orthognathic osteotomies, and their graph depicting the waste time from work to donate. Autologous blood that regression analysis between blood loss and operative is not used is discarded and constitutes waste [26]. Iwase time shows one case with 2750 mL and one case with et al [5] further reported increased intraoperative blood 3400 mL of estimated blood loss. Samman et al [44] loss to be associated with total withdrawn blood before reported on 291 bimaxillary and 69 single-jaw surgical the operation. Retransfused autologous blood has a cases with a range of blood loss between 50 mL and lower hemoglobin concentration and the erythrocyte 5000 mL and 5 hemorrhagic perioperative incidents. function diminishes by 10% per week in unused They reported that 4% of the 291 bimaxillary surgical autologous blood [22]. cases required a transfusion greater than 2 units of While avoiding the risk of transfusion of homologous blood. In the range of blood loss reported by Ash [9], we blood is an advantage of transfusion of autologous find a value of 3400 mL, which occurred in a bimaxillary blood, Moennig et al [51] reported that 3 out of 4 osteotomy case. In the series of Böttger [6], an upper patients needing a transfusion received the available limit of 3400 mL is reported. units of autologous and additional units of homologous blood to compensate the loss. These four patients had 3.8. Criteria for transfusion an average estimated blood loss of 975 mL [51]. Thus, the The updated Cochrane review on transfusion thresholds donation of autologous blood does not entirely exclude [4] concludes that, for most patients, giving less blood is the risk of needing a homologous blood transfusion. safe and blood transfusion is probably not essential until Meta-analyses on preoperative autologous blood hemoglobin levels drop below 7.0 to 8.0 g/dL. In the donation have shown that this practice indeed reduces orthognathic literature, no consensus exists regarding the use of allogeneic blood transfusion by 63%, but what constitutes a blood transfusion ‘trigger’. Fenner et al at the same time increases overall red blood cell [13] performed 105 consecutive bimaxillary osteotomies transfusions (ie, allogeneic and autologous red blood without any need for transfusion and argued that in cell units) by 30% and causes a decline in patient young healthy adults, hemoglobin concentrations as hemoglobin concentration by more than 1 g/dL from low as 50 g/L can be sustained. In contrast, Zellin et al [4] before commencing preoperative autologous blood gave blood transfusion when arterial hemoglobin was donation to immediately prior to surgery [65]. below 100 g/L. Flood et al [63] reported overtransfusion The German recommendation for autologous blood in bimaxillary osteotomies where the postoperative donation states: “The so-called ‘liberal’ transfusion hemoglobin increased after homologous transfusion. indication for autologous blood products stands in Obviously, the high rate of blood transfusion in the series contrast to the strict indication parameters for the of Flood et al [63] could have been avoided by more therapeutic use of blood products laid down in the strict criteria for transfusion. The general condition of the present guidelines and should be rejected because patient and underlying diseases are taken into account it is for all practical purposes equivalent to a blood when deciding on the need for blood cell transfusion, and transfusion without indication” [66]. hemoglobin concentration is one of the criteria [39,64] Donors of autologous blood will more likely receive a used the criterion of allowable blood loss. The allowable transfusion because their initial hemoglobin value has blood loss was defined as 20% of the estimated blood been lowered by the autologous blood donation and volume (male 70 mL/kg, female 65 mL/kg), and once this because the availability of autologous blood influences was reached, a unit of packed red cells was transfused. the decision of transfusion. Puelacher [26] reports that the mean hemoglobin level of 121 patients prior to 3.9. Risk of transfusion donation was 14.2 g/dL and fell to 12.7 g/dL after a mean The authors report that the risk for viral transmission donation of 2.3 units per patient. If then the criterion for is very low in developed countries. An example is transfusion is a certain hemoglobin level, patients with Canada, where the residual risk of transmission through autodonation will sooner reach that level than patients transfusion of HIV, HCV, and HBV is estimated to be 1 per without donation. 7.8 million donations, 1 per 2.3 million donations, and 1 Nath and Pogrel [24] report on 260 orthognathic surgery per 153,000 donations, respectively [4]. This reduction cases in which 126 patients chose autodonation and 134 in risk should lead to the abandonment of the practice patients preferred no autodonation. The transfusion rate of autologous blood transfusion because the most was respectively 26/126 and 3/134 patients, indicating important reason for an autologous blood donation is that the availability of autologous blood influenced the the greatly reduced risk of disease transmission. It has decision to use it. Obviously, ‘a perceived benefit’ must been reported that the availability of autologous blood accompany this decision, which probably is influenced increased the rate of autologous blood transfusion by the information given to the patient. Puelacher et al 48 Stoma Edu J. 2018;5(1): 44-51 http://www.stomaeduj.com BLOODLOSS AND TRANSFUSION NEED IN ORTHOGNATHIC SURGERY: REVIEW OF LITERATURE [26] evaluated 127 questionnaires about autologous and prepared the protocol. CP, JOA and IL were involved Review Article donation of blood in patients who underwent in the analysis of data and the writing of the manuscript. orthognathic surgery; 65 patients (51%) reported All authors read and approved the final manuscript. that autologous blood donation was decisive for the agreement to operate and that 12 patients (9%) would have refused the operation without the possibility of Acknowledgment autologous blood donation. Not applicable. The study was self-funded. There are It should be recommended that the decision to offer the no conflicts of interest and no financial interests to be possibility of preoperative autologous blood donation disclosed. should not be done as a gain-framed or loss-framed persuasive message. A loss-framed persuasive appeal emphasises the disadvantages of failing to comply with References the communicator’s recommendation; in contrast, the 1. Posnick JC, Rabinovich A, Richardson DT. Blood replacement practices for complex orthognathic surgery: a single surgeon's gain-framed appeal will emphasise the advantages of experience. J Oral Maxillofac Surg. 2010;68(1):54-59. doi: 10.1016/j. compliance. Both are well-known techniques in patient joms.2009.07.055. [Full text links] [PubMed] Google Scholar(11) Scopus(6) communication [67]. Obviously, legal recommendations 2. Holty JE, Guilleminault C. 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J Craniomaxillofac Surg. 2001;29(6):360-365. in 92 patients. Patient Saf Surg. 2014;8(1):41-0041. doi: 10.1186/ doi:10.1054/jcms.2001.0248. s13037-014-0041-6. [Full text links] [PubMed] Google Scholar(21) Scopus(7) [Full text links] [Free PMC Article] [PubMed] Google Scholar(11) 63. Flood TR, Ilankovan V, Moos KF, et al. Cross-match requirements Scopus(7) Constantinus POLITIS MD, DDS, MM, MHA, PhD Professor & Chairperson Oral and Maxillofacial Surgery Department University Hospitals Leuven, KU Leuven Leuven, Belgium CV Dr. Politis is an Oral and Maxillo-Facial Surgeon. He is currently a Professor and Chairperson of the Department of OMFS at Leuven University Belgium. He is an invited Lecturer at EHSAL in Brussels. He graduated from the Catholic University of Leuven in medicine (MD) and dentistry (DDS), also specializing in oral and maxillofacial surgery at the same university. There followed additional postgraduate training in Arnhem (Stoelinga), Aachen (Koberg), Copenhagen (Pindborg), Göteborg (Bränemark) and San Francisco (Marx). He also holds a master degree in management (MM) and a master degree in Hospital Management (MHM). He is Secretary General of the Professional Union of Belgian Oral and Maxillofacial Surgeons. Questions 1. The relation between the duration of orthognathic surgery and bloodloss is: qa. Linear; qb. Exponential; qc. Asymptote function; qd. Depends on type of surgical procedure. 2. Which of following measures does not help in minimizing peri-operative bleeding: qa. Anti-Trendelenburg position of the patient; qb. Timely administration of local anaesthesia in Le Fort I; qc. Replacing the saw by piezo-tome; qd. Control of body temperature. 3. The overestimation of the hemoglobin drop measured after orthognathic surgery can be due to: qa. Hemodilution; qb. Weight of the patient; qc. Body temperature; qd. Hypertension. 4. The risk of blood transfusion includes transmission of all of following agents but one: qa. Hepatitis B; qb. Hepatitis C; qc. HIV; qd. Syphilis. Stomatology Edu Journal 51