Abstract
The aim of this trial was to compare two techniques of maxillary dysjunction, with 10 mg/kg tranexamic acid as an adjuvant, in isolated non-segmented Le Fort I procedures. Two hundred patients were randomized to one of four groups: group A, pterygomaxillary dysjunction + saline; group B, tuberosity separation + saline; group C, pterygomaxillary dysjunction + tranexamic acid; and group D, tuberosity separation + tranexamic acid. Primary outcome measures were intraoperative blood loss and operating time, while the secondary outcome measures were surgical field assessment, need for blood transfusion, and duration of hospitalization. The data were analyzed using one-way analysis of variance (SPSS v. 17.0), and the level of significance was set at P < 0.05. Results revealed that group D (tuberosity separation + tranexamic acid) had the least blood loss (mean 172 ml) and shortest operating times (mean 49 min), with the best surgical field. This group also exhibited the lowest drop in postoperative haemoglobin concentration (Hb gm/dl) and packed cell volume (PCV). Five patients, all in group A, required a blood transfusion and had an extra 24 h of hospitalization. This trial revealed that the tuberosity separation technique with the use of tranexamic acid was the best protocol in producing the least blood loss, minimizing the operating time, and providing the best surgical field.
The Le Fort I osteotomy is a workhorse procedure for midface skeletal correction and is one of the most common procedures practiced by a range of surgeons with varied surgical experience. The blood loss in this elective procedure is a nagging complication that has been reviewed extensively in the literature. The need to make the procedure safe and predictable is paramount.
The surgical technique of the Le Fort I osteotomy has undergone various modifications and changes since the initial description by von Langenbeck in 1859. Bell et al. introduced the curved osteotome for pterygomaxillary separation, and Schuchardt in 1942 was the first to down-fracture a maxilla for a corrective procedure. Trimble and Tideman introduced a modification to the classic pterygoid plate dysjunction in which the posterior osteotomy was completed through the maxillary tuberosity or third molar socket. The authors claimed that this method was a safer technique and was associated with less blood loss, as it avoided the pterygoid area completely. Since bleeding is a major concern in Le Fort I osteotomy, the quest for the best method of its reduction is still ongoing. Hypotensive anaesthesia is now an established method for the same, as it is said to reduce blood loss by up to 40%.
Pharmacological agents have also been used in the recent past as adjuvants in various procedures to aid in the reduction of blood loss. Among these, tranexamic acid has been proven to efficiently reduce bleeding in Le Fort I osteotomies. Tranexamic acid is a synthetic derivative of the amino acid lysine, which exerts its anti-fibrinolytic effect through reversible blockade of lysine binding sites on plasminogen molecules. It has been employed as an effective method of reducing blood loss for orthognathic surgical procedures. Various authors have proposed different methods of administration and dosing with regard to the use of tranexamic acid in such patients.
The aim of this clinical trial was to compare pterygoid dysjunction with Trimble’s tuberosity separation technique, with or without the use of tranexamic acid, to determine the best possible protocol to reduce intraoperative blood loss and the operating time during Le Fort I procedures.
Materials and methods
This prospective, triple-blind, randomized trial was carried out on patients undergoing Le Fort I osteotomy in three different speciality maxillofacial centres in South India.
Blinding and randomization
Randomization was done by block method to ensure unbiased case selection by equal distribution. Patient enrolment is shown in a flow chart in Fig. 1 .
Triple blinding was achieved to eliminate any bias. The investigator, the anaesthetist, and the surgeon were blinded to the subgroup to which the patient belonged. Three surgeons across the three centres, with similar levels of experience (consultants) and surgical skill in performing orthognathic surgical procedures, were part of the trial. The test solution was supplied by someone who was independent of the trial.
Group A patients received a placebo of saline (5 ml) and underwent classical pterygomaxillary separation. Group B patients received placebo saline and underwent tuberosity separation. Group C patients received 10 mg/kg tranexamic acid (Trapic 5 ml ampoules, Sun Pharmaceuticals, India) and underwent classic pterygomaxillary separation. Group D patients received 10 mg/kg tranexamic acid and underwent tuberosity separation. Tranexamic acid was administered at a dose of 10 mg/kg in a slow intravenous infusion with saline 30 min prior to anaesthetic induction and was discontinued during closure.
Ethical approval and clearance was obtained from all of the institutional ethics committees. Informed consent was also obtained from all patients included in the trial.
Inclusion and exclusion criteria
Patients undergoing an isolated non-segmental Le Fort I osteotomy regardless of final repositioning, who were aged 18–35 years, who consented to the trial, and who were American Society of Anesthesiologists (ASA) I status were included in this trial. These criteria were applied across all centres.
Patients with cleft lip and palate, syndromic deformities, ASA II status or higher, pregnant or lactating mothers, patients on medication that could alter bleeding, patients with bleeding and clotting disorders, patients who refused consent, and patients with a known drug allergy to tranexamic acid were excluded from the trial.
Mean arterial pressure (MAP) was maintained between 60 and 70 mmHg in all groups as a measure of hypotension achieved. If any patient’s MAP exceeded 70 mmHg during the surgery they were also excluded from the trial based on a failure to maintain intraoperative hypotension.
Anaesthetic protocol
Patients were induced with an induction agent and a skeletal muscle relaxant, with an appropriate sized endotracheal tube. The anaesthetic protocol followed in all subjects is elaborated in Table 1 . All patients received hypotensive anaesthesia using 100 μg of intravenous nitroglycerine. During surgery the plane of anaesthesia was maintained with vecuronium bromide (the skeletal muscle relaxant) and the anaesthetic agents N 2 O:O 2 (60:40). Patients were positioned with 15 degrees head end elevation. Prior to incision, which was made using cautery, 2% lignocaine with 1:80,000 adrenaline was injected.
| Drug | Dose | |
|---|---|---|
| Induction | Sodium thiopental | 5 mg/kg |
| Analgesic | Fentanyl | 100 μg/kg |
| Muscle relaxant | Vecuronium bromide | 0.1 mg/kg |
| Volatile agent | Isoflurane | 1% |
| Test drug (groups C and D) | Tranexamic acid | 10 mg/kg |
| Test drug (groups A and B) | Saline | 5 ml |
Preoperative evaluation
The preoperative evaluation of all patients included packed cell volume (PCV) and haemoglobin concentration (Hb gm/dl), along with bleeding and clotting times. Induction blood pressure and MAP were also noted. Variables recorded included postoperative Hb gm/dl and PCV (after 24 h) and total blood loss in the suction container and gauze minus the volume of saline used. The intraoperative surgical field was assessed using Fromme’s ordinal scale by the operating surgeon. Fromme’s ordinal scale scores the surgical field from zero to five; zero denotes a virtually bloodless field and five denotes massive bleeding requiring discontinuation of the surgery.
Parameters assessed
Primary outcome measures were (1) total blood loss (timeframe: intraoperative period); (2) total operating time (timeframe: incision to closure).
Secondary outcome measures were (1) drop in Hb (preoperative Hb − postoperative Hb gm/dl); (2) drop in PCV (preoperative PCV − postoperative PCV); (3) surgical field assessment (tool: Fromme’s ordinal scale); (4) need for postoperative blood transfusion (Hb less than 8 gm/dl); (5) duration of hospital stay (admission to discharge).
The data were analyzed using one-way analysis of variance (ANOVA). The level of significance was set at P < 0.05. The analysis was carried out using SPSS version 17.0 software (SPSS Inc., Chicago, IL, USA).
Results
A total of 224 consecutive patients were evaluated for the study. Twenty-four were excluded due to ASA II status or higher ( n = 4), increased intraoperative MAP over the set limit of 70 mmHg ( n = 10), refusal to consent to the trial ( n = 2), cleft lip and palate ( n = 5), and age >35 years ( n = 3). Thus 200 patients from the three centres were randomized to four groups; centre 1 contributed 96 patients, centre 2 contributed 72 patients, and centre 3 contributed 32 patients. Fig. 1 provides a summary of the patient recruitment process. The patients ranged in age from 18 to 35 years.
There was no significant difference between the patient groups in terms of demographic data. There were 108 female patients and 92 male patients enrolled in this trial. Table 2 provides the descriptive data from the preoperative assessment. Table 3 provides the results of the primary and secondary variables. A P -value of <0.05 was taken to be statistically significant.
| Group A Saline + dysjunction |
Group B Saline + tuberosity separation |
Group C Tranexamic + dysjunction |
Group D Tranexamic + tuberosity separation |
P -value a | |
|---|---|---|---|---|---|
| Age, years | 22.84 (4.506) | 24.40 (4.262) | 25.16 (4.593) | 22.84 (4.478) | 0.176 |
| Bleeding time, s | 313.40 (27.107) | 313.20 (47.846) | 313.12 (34.383) | 314.03 (42.942) | 1.000 |
| Clotting time, s | 582.80 (53.503) | 575.60 (58.100) | 583.75 (56.090) | 578.077 (57.966) | 0.950 |
| Induction MAP, mmHg | 96.08 (2.871) | 96.36 (3.289) | 94.16 (4.697) | 96.46 (3.880) | 0.114 |
| Lowest MAP, mmHg | 62.40 (1.633) | 62.84 (1.700) | 62.29 (1.654) | 62.15 (1.713) | 0.502 |
| Preoperative Hb gm/dl | 12.61 (1.391) | 12.65 (1.682) | 13.33 (1.683) | 12.51 (1.245) | 0.215 |
| Preoperative PCV gm/dl | 37.86 (4.087) | 37.84 (4.786) | 40.00 (5.054) | 37.52 (3.736) | 0.191 |
| Group A Saline + dysjunction |
Group B Saline + tuberosity separation |
Group C Tranexamic + dysjunction |
Group D Tranexamic + tuberosity separation |
P -value a | |
|---|---|---|---|---|---|
| Postoperative Hb gm/dl | 9.96 (1.376) | 10.53 (1.600) | 11.13 (1.453) | 10.93 (1.317) | 0.028 |
| Drop in Hb gm/dl | 2.66 (0.758) | 2.12 (0.725) | 2.21 (0.581) | 1.56 (0.585) | 0.001 |
| Postoperative PCV gm/dl | 29.95 (4.177) | 31.63 (4.766) | 33.41 (4.359) | 32.71 (3.950) | 0.034 |
| Drop in PCV gm/dl | 7.91 (2.362) | 6.22 (1.827) | 6.66 (1.748) | 4.84 (1.844) | 0.001 |
| Total blood loss, ml | 412.00 (69.761) | 330.00 (40.104) | 253.08 (54.055) | 171.92 (44.096) | 0.001 |
| Total operating time, min | 96.60 (18.184) | 64.60 (11.895) | 71.87 (19.099) | 49.23 (10.834) | 0.001 |
| Surgical field assessment score | 2.64 (0.489) | 1.96 (0.200) | 1.5 (0.5989) | 1.11 (0.325) | 0.001 |
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