Incidence , Clinical Characteristics and Blood Transfusion Factors of Elderly Patients undergoing Orthopedic Surgery in a Tropics University Hospital

Copyright: © 2016 Mahoungou Guimbi KC, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. *Corresponding author: Mahoungou Guimbi Kryste Chancel, Department of Surgery and Maternity, University of Marien Ngouabi, Brazzaville, Congo, Tel: 00242055233281; E-mail: mahoungouguimbi@yahoo.fr


Introduction
The decline in world poverty is accompanied by an increase in life expectancy in both the so-called rich countries and in developing countries. This correlates to the presence of more and more elderly people in the general population. It is then becoming more common to see anesthesia and surgery for the elderly. In the West, orthopedic and trauma surgery is primarily interested in the elderly [1][2][3][4]. In developing countries this surgery focuses on young subjects, the share of activity assigned to the elderly is often misjudged [5,6]. The purpose of this work is to highlight the clinical features of elderly underwent orthopedic surgery and identifies clinical factors associated with blood transfusion for them.

Patients and Methods
This is a retrospective study over 24 months among patients undergoing orthopaedic surgery after local ethics committee approval. Of this group, we excluded patients under 60 years old, according to the definition of the elderly in our environment [7]. Thus, of the 305 patients involved in the orthopedic surgery, 64 (21%) were of an age ≥ 60 years. The variables studied initially focused on demographic and clinical characteristics of patients, and in a second step we analyzed the influence that these variables could exert on blood transfusion. For statistical analysis, quantitative variables were expressed as mean ± standard deviation and categorical variables as numbers and percentages. Transfusion clinical determinants were sought from the set of clinical factors that could lead to blood transfusion, by simple logistic regression. Then, in a second step, all

Results
The average age of patients was 70.8 ± 7.1 years (range 60-88 years). Twenty-two (34.4%) patients were aged 75 and over. The sex ratio [M/F] was 0.73. The presence of comorbidities concerned 33 (51.6%) patients. These were dominated by hypertension, diabetes mellitus and a previous stroke with a respective frequency of 39.1%, 7.8% and 6.3%. In addition, 14 (21.9%) patients were receiving long-term treatment for chronic conditions (Table 1). Treatment with calcium channel blockers (10.9%) and vasodilators (4.7%) were at the forefront.

Discussion
The incidence of orthopedic surgery in the elderly aged 60 years-old or more in our study was 21%. This rate varies in developed countries between 18 and 70% [8][9][10]. This confirms the progressive aging of the population in developing countries. This population aging phenomenon correlated to the emergence of chronic diseases within it. Thus, 51.6% of patients in our study have at least one chronic disease. Hypertension (39.1%), diabetes mellitus (7.8%) and history of stroke (6.3%) were at the forefront (Table 1). Similar results were reported in the literature. For Herrera et al. [11], chronic underlying disease was mainly vascular (69.2%), endocrine and metabolic (50.8%), heart (38.3%) and neurological (35.8%); whereas Brauer et al. [12] chronic heart failure, chronic obstructive pulmonary disease and diabetes mellitus were the main comorbidities.
Patients of ASA class 2-3 numbered 37 (57.8%) while ASA class 1 included 27 (42.2%). The distribution of patients according to the ASA classification could influence long term treatment frequency, class 2-3 was associated with comorbidities will explains the observed rate of these treatments. Similar distribution rates relative to similar classes ASA have been reported in literature [10][11][12][13][14][15]; whereas for Martinez et al. [2] the median age of patients was 61.6 years and ASA class 1 with 213 (70.5%) patients was predominant. Regarding anesthetic techniques, loco-regional anesthesia was administered to 48 (75%) patients, with 91.6% of cases of spinal anesthesia. The use of nerve blocks was marginal at 8.3% of cases. Sedation accompanied loco-regional anesthesia in 5 (10.4%) of cases. General anesthesia was applied to 16 (25%) patients. Propofol (62.5%) was the main hypnotic and vecuronium (68.7%) the main myorelaxant agent. In the literature, the frequency of general and loco-regional anesthesia in orthopedic surgery varies. Many authors observed the same distribution between loco-regional and general anesthesia as us, in contrast other authors reported a greater propensity for general anesthesia [10,16,17]. Intra-operative hypotension (29.7%) and hemorrhage (4.7%) as major intra-operative incidents identified in this study have also been identified by a number of other authors [11][12][13]. As the top surgical indication, the majority of patients were operated on lower limbs (85.9%) and osteosynthesis (57.8%). In a study conducted in Spain involving patients of 65 years and older admitted for orthopedic hip surgery, DHS (Dynamic Hip System) plate and intermediate hip prosthesis were the most commonly used techniques. The incidence of bone synthesis was low, 5% of all indications [11].
The blood transfusion rate was high, 37.5%. This rate, however, appears high compared to those reported in the United States [3]. Blood conserving technologies are highly developed in these countries and this could justify these lower transfusion rates. Moreover, in this US study, the age of 60 years, female gender, comorbidities and other criteria within the hospital structure were presented as risk factors for blood transfusion [3]. Older age and female sex were considered as factors increasing the risk of transfusion after hip arthroplasty [18,19]. Furthermore, blood transfusion, the occurrence of intra-operative incidents and increased operative time were associated with the practice of general anesthesia after a multivariate analysis [16]. In our study, age ≥ 60 years (OR=2.04, 95% CI: 1.13 to 3.68, p=0.01), duration of surgery (OR=1.02, IC 95% from 1.01 to 1.03, p<0.0001), the presence of intra-operative events (OR=6.69, 95% CI: 3.77   Open Access 3 to 11.90, p<0.0001), regional anesthesia (OR=2.19; 95% CI: 1.10 to 4.34; p=0.02) were risk factors for transfusion blood cells in a simple logistic regression model. General anesthesia (OR=0.43, 95% CI: 0.22 to 0.82, p=0.01) had rather a protective effect (Table 2). In the multiple regression model, age ≥ 60 years (OR=5.33, 95% CI: 2.11 to 13.42, P=0.0004), duration of the surgery (OR=1.02, 95% CI: 1.01 to 1.03, p <0.0001) and intra-operative events (OR=5.07, 95% CI: 2.34 to 11.00, p<0.0001) were independent risk factors determining blood cells transfusion. Long-term treatment (OR=0.77, 95% CI: 0.20 to 2.93, p=0.71) and general anesthesia (OR=0.63, 95% CI: 0, 10 to 3.94, p=0.62) were non-significant protective factors. There were no similar data available in Africa for comparison.

Conclusion
Anesthesia in orthopedics in the elderly aged 60 or higher highlights a high frequency of comorbidities, a propensity for implementing loco-regional anesthesia techniques and a frequent tendency towards blood transfusion. Age ≥ 60 years, duration of the surgery and intraoperative events are clinical factors associated with intra-operative blood transfusion.