AUTOLOGOUS BLOOD TRANSFUSION IN PATIENTS UNDERGOING HIP REPLACEMENT SURGERY

INTRODUCTION
Autologous blood transfusion is a set of procedures done in order to collect a patient's blood and reinfuse it during or after a surgical intervention. The aim is to meet the patient's need for blood products without allogeneic transfusion. By observing the hemoglobin and hematocrit values during blood donation in the pre-operative and post-operative period and by counting transfused blood units, the aim of this article was to detect whether there was any difference between the patients receiving autologous blood and those receiving only allogeneic blood.


MATERIAL AND METHODS
This prospective study was performed at the General Hospital "Dorde Joanović" Zrenjanin from October 24th, 2011 to January 24th, 2013. The study included 60 patients who were divided into the experimental group of 30 patients who had been transfused autologous blood and the control group of 30 patients who had been transfused only allogeneic blood.


RESULTS
The average values of hemoglobin and hematocrit in the first and the second donation were 148.9 g/l and 44.2%, and 138.7 g/l and 40.8%, respectively. Oral iron preparation was given to 12 patients for two weeks before the first donation. The level of hemoglobin and hematocrit in both groups of patients had approximately the same values in the pre-operative and post-operative period. In the post-operative period, 2.53 units were transfused per patient in the experimental group and 3.73 units were transfused per patient in the control group.


CONCLUSION
Administration of pre-operatively donated autogenous blood reduces the number of transfused deplasmatised erythrocytes units in comparison to the number of units transfused to the patients receiving only allogeneic blood products. The pre-operative use of oral iron preparations increases hemoglobin values significantly.


Introduction
Anterior cruciate ligament (ACL) injuries represent a significant epidemiological problem in the world.A group of American authors [1] has determined the incidence of acute ACL injuries to be 1:3000 per a year.The number of recorded cases in USA per year has doubled from 100 000 to 200 000 in the last 5 years, so has the number of performed reconstructions, from 50 000 to 100 000 [1].This fact has provoked much greater interest of authors for ACL traumatology.However, it is illogical that incomparably greater number of studies [2] are focused on the development of surgical techniques than on the analysis of injury causes, risk factors and injury prevention .
The reason for a larger number of recorded ACL injuries lies in a greater number of sportsmen, especially women (who are at a 2-9 times greater risk of ACL rupture in comparison to men) [5][6][7][8][9], development of diagnostics [2] (especially MRI), greater interest of physicians for these injuries, and because of the development of surgical techniques and excellent postoperative results [1,2].There is also greater effort of experts to define the cause of injury with the most risk and to find proper training methods to prevent sport knee injuries.The aim of this study was to find specific risk factors and causes of ACL injuries in the Republic of Serbia.

Material and methods
The study included 451 patients surgically treated at Orthopedic Surgery and Traumatology Clinic in Novi Sad from 2006 to 2008.The study sample consisted mostly of men, 320 (71%), 131 were female patients (29%), and their age ranged from 15 to 49, the average age being 24.Of 451 patients in this sample 90% were younger than 35 years of age.
The left knee was injured in 235 patients (52%), and the right knee in 216 (48%).The height of the patients ranged from 163 cm to 204 cm, the average being 181 cm.The weight of the patients was in the range from 52 kg to 135 kg, the average being 80.23 kg.
All of the participants volunteered to fill in an anonymous questionnaire consisting of the following groups of data: 1. Age, sex, profession, demographic data, and education.
3. Sport structure (kind of sports, duration of career, competing rank), competing level.
4. Previous knee injuries, diagnostics, and ways of treatment.
5. Current knee injury (symptoms) 6.The cause of injury, training analysis (game phases), and way of getting injured.
7. The type and quality of the sport field and footwear, immobilization, and state of the musculature.
8. Previous illness, nutrition, daily therapy use, genetic profile.9. Period from getting injured to making a valid diagnosis, initial therapy after the injury.
10.Period from injury to surgical treatment.
Most of the sportsmen in our study sample mentioned that they had been adequately physically prepared before the injury; especially 312 of them (72%), among those mostly active, with the warm up supervised by a coach.Among 81 of them (22%), who did not have an adequate physical preparation, there were 74 recreationists and 7 active ones.These 7 sportsmen risked their professional careers by going in for some other recreational sports (soccer, skiing, sky diving), without previous warm up.Out of 64 injuries which occurred at the training sessions, 6 (10%) happened during the warm up and at the beginning of the session; 41 (63%) happened in the middle of the session and 17 (17%) towards the end of the session.Out of 189 competitive game injuries, ACL injuries occurred during the warm up in 9 of them (5%), at the beginning of the game in 40 (21%).Injuries occurred much more often in the middle of a game (in 86 patients-46%) and towards the end (in 54 patients-29%).
Out of 260 active sportsmen, 192 (74%) had one training session a day and 68 (26%) trained twice a day.A training session lasted from 45 to 150 minu tes, mostly 90 minutes in 159 sportsmen (61%).Even though 140 patients went in for sports only for recreation, 21 patients (15%) were active once a day; 38 (27%) had trainings twice a week and 81 patients (58%) at least three times a week.
Previous illnesses were recorded in 44 patients.Every day therapy for other illnesses, mostly bronchodilatators and NSAID, was taken by 10% of the patients and 107 subjects took no therapy (90%).Only 37 (8.3%) of the patients mentioned previous family history of ACL rupture (29 next-of-kin, 6 cousins and 2 relatives).
Out of 400 sportsmen, 26 (7%) had a specific diet: 21 of them were on their own diet, and 5 of them were on a diet prescribed by the club doctor.93% of them had a standard diet.According to the body mass index (BMI), 59% of them were normally nourished, 32% were obese, and 9% were malnourished.
Sport injuries, being the most common causes, were recorded in 88% of the cases; 47 ACL ruptures happened while performing everyday activities (11%), and traffic accidents caused 4 ruptures, mostly with some other complex injuries, accompanied by other knee joint structures.
ACL ruptures caused by sport activities were recorded in 400 patients (Graph 1).Injuries with no contact with other athletes occurred in 312 (78%) patients, mostly: volleyball/basketball/handball players, gymnasts, and skiers.Contact injuries (hitting the knee and back of the lower leg during the knee extension or hitting the front of the upper leg) happened in 88 (22%) patients, mostly in martial arts fighters and soccer players (Graph 2).Most of the sportsmen, 144 (36%), got injured while landing after jumping in sports like volleyball, basketball, handball and even soccer; whereas 116 sportsmen (29%) got injured while changing the direction, running, or sudden running starts, 20 (5%) were injured because of a sudden stoppage (deceleration), especially in soccer, and 32 (8%) because of over extension of the lower leg.
The most common causes of ACL injuries among different sports are presented in Graph 3.

Discussion
The incidence and severity of ACL injury has been on the rise in the last few decades.At the same time there is a need in terms of demystifying risk factors, cause analysis, and finding out adequate training processes to prevent knee injuries.There are many inconsistencies in terms of significance of some risk factors [3].
The age of the patients in our study sample ranged from 15 and 49, which is in accordance with Woo's epidemiologic data [4].Stevenson and Orchard studies [5,6], have proven higher injury incidence in older sportsmen, whereas our and Geli's study [7] have shown that incidence was higher in younger sportsmen because 90% of our surgically treated patients were younger than 35 years of age.Knee ligament injuries are the most frequent (90%) in the period before the second and fourth life decade [4].
The majority of our subjects came from an urban environment, which can be explained by the fact that most of elite sports clubs are located in towns and cities, which offer better conditions for professional engagement in sports than rural environments.
In our study sample of active sportsmen, ACL ruptures occurred 3 times more often during competition than training sessions because of more aggressive and riskier types of movement resulting in higher risk of getting injured.Competitive games presented 2.7 times higher risk than friendly games/matches, which also speaks in favor of the fact that injury occurs more often in important games.The injuries occur 3.8 times more often in the middle and final parts of the games, when the strain on the knee is the greatest, and when players are more concentrated on the result.Ekstrand et al [8] have stated that injuries occur 2 times more often during soccer games than during training sessions.Myklebust et al [9] and Seil et al [10] have concluded that ACL ruptures occur 30 and 24 times more often during handball matches than during training sessions respectively.
In our study sample, majority of injuries occurred on the floor (45%) because of the fact that handball, basketball and volleyball matches are almost always played indoors.ACL ruptures occurred on dry court (79%), which represented higher risk in contrast to muddy, slippery, wet and frozen fields because of the foot being fixed to the ground and under the influence of rotary forces on the knee.Powell et al [11] pointed to higher incidence of knee injuries on artificial surfaces in contrast to grassy and sand surfaces (beach volleyball), because of the higher friction level between the feet (footwear) and artificial grass.Lambson et al [12] carried out a study including 3119 high school American football players and showed a statistical significance of ACL rupture incidence in players who competed on natural surfaces and wore specially designed sports footwear not allowing torsion of the feet on the ground thus enabling rotary forces to affect the knee and causing ACL injuries.However, both Barrett's study [13] and ours have showed no correlation between footwear type and injury.
Due to the fact that the study sample consisted predominantly of sportsmen (59% of normally nourished patients), BMI had no significant influence on ligament rupture, although injuries occurred more often in obese subjects than in normally nourished ones, which is generally the case in the population of Vojvodina.Out of 451 study subjects, 135 had increased their body mass from 1 to 10 kg in the period of 6 months prior to the injury (4.87kg on average), which could indirectly show that 30% of the subjects had not been ideally fit prior to the injury.BMI was recorded as a risk factor in studies of Orchard and Jones [6,14], while no correlation between BMI and incidence was observed in other 9 studies [15][16][17][18][19][20][21][22][23].
Higher demands for world class sport results in women are followed by a higher incidence of ACL injuries in women.Although there were 2.4 times less women in our study sample, their proportional number of injuries is increasing both in the world and in our country.So, the percentage of women with ACL reconstruction was 19% in Novi Sad in 2005, whereas in 2008 it rose to 29% (in our study).In addition, sportswomen are at a 2-9 times higher risk of getting ACL injuries than men according to some studies [3][4][5][6][7]15,16,[19][20][21].Anatomic differences can be a predisposing factor for higher incidence of injuries among women [7], because of their wider pelvis [3,5,6], increased knee valgus [6,7,[19][20][21], increased external tibial rotation [6,7,[19][20][21], narrower femoral intercondylar notch [3,[5][6][7], smaller ligament dimensions [3,5,6], weaker neuromuscular response [15,17], higher ligament laxity [15,17], and hormonal variations during menstrual cycle [15].Hewitt [15] observed that the highest number of ACL lesions occurred in the period of ovulation and that women on oral contraceptives were at a higher risk of getting injured.In our sample, only 6% of women mentioned using oral contraceptives prior to the injury, which does not speak of a significant correlation with ACL lesion, but that women in Serbia do not use this kind of pregnancy prevention as much as in the world.
In our study sample, persons active in sports are 8 times more often injured than inactive ones.ACL injuries did not occur in those beginning an activity, and surgery was not performed on any patients who had not been at least recreationally active for 2 years.Peterson et al [16] have proved that sportsmen less physically fit are at a higher risk of getting injured and the results of our study, as well as those of Hopper et al [17] and Hosea et al [18], have proved that injuries occurred mostly in sportsmen with long careers.
More than three quarters of ACL injuries occurred in the most popular sports in Vojvodina (Serbia): soccer, handball, and basketball.Unlike Serbia, the riskiest sports in Scandivanian countries are handball and skiing [19,20] and football and basketball in the USA [16,17].
The limitations of this study are connected with subjectivity of patients when answering the questionnaire and because of the lack of video material to objectivize the analysis of the most frequent causes and mechanisms of getting injured.Our survey is comparable with similar ones [24,25] and creates conditions for prevention of ACL injuries.

Conclusion
Young population active in sports is at the highest risk of getting an anterior cruciate ligament injury.
Our study has shown that anterior cruciate ligament injuries happen most often in football players, than in handball/basketball/volleyball players and martial arts fighters, whereas active basketball players are at the highest risk of getting injured.
Our study has not shown statistical significance of correlation between anterior cruciate ligament lesion and footwear type, body mass index, warm up, previous illnesses, everyday therapy and genetic profile.
Anterior cruciate ligament injuries are more frequent in sportsmen with longer career, during matches rather than training sessions, in the middle or by the end of a match or game, on dry surfaces, without a contact with other competitors, when landing and changing the direction of movement.
By defining risk factors, injury cause analysis, and education of physicians, sportsmen and coaches, conditions for preventing injuries of anterior cruciate ligament can be created.