Influence of the timing of hip fracture surgery on final treatment outcomes

Introduction: Globally, the incidence of hip fractures has had an increasing trend, due to longer life expectancy. It is estimated that, by 2050, it will have reached 6.26 million cases a year. The aim of our review is the analysis of available literature on the relationship between the timing of hip fracture surgery and its impact on morbidity and mortality.

Results: Over 85% of patients who suffer hip fracture are individuals older than 65 years with existing comorbidities. Even with adequate and optimal treatment, age and comorbidities predispose these patients to a worse prognosis and higher morbidity and mortality, as compared to the general population. The official position of AAOS is that patients who are operated on within 48 hours of hospital admission have a better treatment outcome. The reasons for delaying surgical treatment can be divided into medical and nonmedical. A large number of published studies support the claim that patients who are operated on 24 hours within hospital admission have a better outcome in terms of complications and mortality (after 30 days and after one year) than patients who are operated on later. On the other hand, several retrospective studies and meta-analyzes have shown that there is no significant difference in mortality between patients operated on 24 h, 36 h, and 48 h after admission. However, in these studies, surgical treatment within 4 days of admission has been identified as the most significant factor correlating with reduced mortality.

Conclusion: Patients with hip fractures should be operated on within 24 hours of admission unless they have an acute medical condition that prevents surgery. If there is a medical condition that can be corrected, this window is prolonged to 48 hours, but the waiting time for surgical treatment should not be longer than 4 days.

INTRODUCTION

Globally, the incidence of hip fractures has had an increasing trend, due to longer life expectancy. It is estimated that, by 2050, it will have reached 6.26 million cases a year, which is an immense increase from 1.6 million cases a year, registered in 1990 [1]. It has been estimated that mortality within the first year after hip fracture can be as high as 58% [2].

The link between surgery timing, on the one hand, and morbidity and mortality, on the other, remains controversial. The lack of official protocols and recommendations represents a significant obstacle to forming a universal view regarding the appropriate time from patient hospital admission to surgical treatment.

 Perioperative evaluation of the patient’s condition, as well as the availability of an operating theatre, represent the most common reasons for delaying surgery [3]. Due to the fracture itself and prolonged immobility, patients with hip fractures are at increased risk of developing thromboembolic complications, urinary infections, pneumonia, and decubitus ulcers [4]. Available studies show conflicting results, which is why trauma centers all over the world have developed protocols of their own on the treatment of patients with hip fractures.

The aim of our review article is to perform an analysis of available literature related to the link between the timing of hip surgery and its influence on morbidity and mortality.

HIP FRACTURE COMPLICATIONS

 Over 85% of patients who suffer hip fracture are individuals older than 65 years with existing comorbidities [5]. Even with adequate and optimal treatment, age and comorbidities predispose these patients to a worse prognosis and higher morbidity and mortality, as compared to the general population.

The ASA Classification (American Society of Anesthesiologists Physical Status Classification System) is considered a good tool for assessing perioperative risk [6]. One study showed that patients with an ASA 3 score had a 3.78 times higher risk of developing perioperative complications, as compared to patients with an ASA 2 score, while patients with an ASA 4 score had a 7.39 higher risk of complications, as compared to patients with an ASA 2 score [7].

The most common perioperative complications of hip fracture are the following:

1. Cognitive and neurological impairments (10%, mainly patients older than 65 years, postoperative delirium)
2. Cardiopulmonary events (myocardial infarction – MI; deep vein thrombosis – DVT; pulmonary thromboembolism – PTE; pneumonia)
3. Gastrointestinal disorders (dyspepsia, constipation)
4. Urogenital complications (urine retention, urinary infection – risk factor for the development of delirium)
5. Hematological complications (anemia)
6. Electrolyte and metabolic imbalance
7. Decubitus ulcers [4].

In patients with a high ASA score and patients treated conservatively, studies have shown increased mortality, a year after the injury/surgery [8],[9],[10]. Also, another study showed that, in medically unstable patients, postponing surgical treatment did not lower mortality, as compared to patients who were operated on within 4 days of hospital admission.

POSTPONING SURGICAL TREATMENT AND MORTALITY

The official position of the American Academy of Orthopaedic Surgeons (AAOS) is that patients surgically treated within the first 48 h of hospital admission have a better treatment outcome [11]. The reasons for postponing surgical treatment can be categorized as medical or nonmedical.

Unavailability of an operating theatre or unavailability of an orthopedic surgeon on duty, unavailability of adequate implants, as well as the lack of an orthopedic and traumatology department in some hospitals, are all nonmedical reasons for postponing surgery [12]. In such cases, patients who are, from the medical point of view, ready for surgery, must wait until an operating theatre, or an orthopedic surgeon, or an implant are made available, or even until transport is organized to a different hospital, which has an orthopedic and trauma surgery department. All of the above stated may delay surgery by more than a day, and studies have shown that, even in patients ready for surgery, who suffer no medical conditions that need urgent treatment, a waiting period longer than 4 days of the day of hospital admission and the resulting immobility, may lead to serious consequences and a rise in mortality [13].

In their study, Sheehan et al. demonstrated that patients admitted to hospitals with lesser resources are faced with a longer waiting period from hospital admission to surgery, for nonmedical reasons, and that their consequent exposure to prolonged immobilization and inflammatory conditions may lead to fatal consequences for the patient [12].

Preoperative patient preparation, i.e., patient stabilization, is a medical reason for delaying surgery [14].

A large number of published studies support the position that patients who are operated on within the first 24 h of hospital admission have a better outcome with regards to the development of complications and mortality (after 30 days and after a year) than patients who are operated on later [9],[15],[16],[17],[18],[19],[20]. One study showed that it was justified to delay surgery up to 48 h of hospital admission in patients suffering from an acute medical condition that could be dealt with quickly, but that, in case of patients who suffered from a chronic condition that could not be remedied within 48 h of admission, delaying surgery did not decrease mortality, as compared to patients from the same ASA category which were operated on within 48 of admission [20].

In a retrospective study, which involved 116 older patients with hip fracture, Mutlu et al. concluded that, in patients with hip fracture, unnecessary cardiological tests led to surgery delay, thus potentially leading to the development of complications, while, at the same time, leading to no significant changes in perioperative cardiological therapy [21].

 In a meta-analysis comprising 35 independent studies, involving 191,873 participants and registering 34,448 lethal outcomes, Moja et al. proved that early surgery (within 24 h of admission or 48 h of admission, at the latest) led to a decrease in the risk of a lethal outcome (p < 0.001) and in the risk of decubitus sores (p < 0.001), concluding, therefore, that orthopedic surgeons must strive towards performing surgery on most patients with hip fracture within 24 h to 48 h of hospital admission [22].

In a meta-analysis involving 4,208 patients, with 721 lethal outcomes, Simunovic et al. concluded that early surgery (up to 72 h of admission) led to a significant decrease in mortality (p = 0.01), decreased the risk of pneumonia (p = 0.02), and led to a decreased risk of the development of decubitus sores (p < 0.001) [23].

On the other hand, several retrospective studies and meta-analyses showed that there was no significant difference in mortality between patients surgically treated 24 h, 36 h, and 48 h after hospital admission [13],[24],[25]. However, in the said studies, surgical treatment within 4 days of hospital admission was identified as the most significant factor correlating with reduced mortality [13].

Due to all that has been stated above, individual countries adopt national guidelines on justified surgical treatment delay, in order to improve the final treatment outcome. Thus, the UK National Institute for Health and Care Excellence has proposed that surgical treatment may be postponed in patients with the following medical conditions: anemia < 8 g/dl, correctable coagulopathies, hypovolemia, electrolyte imbalance, uncontrolled diabetes, uncontrolled heart failure, acute cardiac arrhythmia or ischemia, acute chest infection, or exacerbation of chronic chest infection, until a time that these are remedied [12].

SURGICAL TREATMENT AND LENGTH OF HOSPITAL STAY

 Patients operated on earlier spend less time in hospital; they are verticalized sooner in relation to the day of admission; their functional recovery is more efficient, while treatment costs are smaller [26].

In a prospective study, involving 850 patients, Al-Ani et al. found that, in patients who were operated on within 24 h, 36 h, or 48 h of hospital admission, the length of hospital stay was shortened in the following manner: for the group of patients surgically treated within 24 h of hospital admission – 14 days vs. 18 days for those operated on later; for the group of patients operated on within 36 h of hospital admission – 15 days vs. 19 days for those operated on later; and for the group of patients operated on within 48 h of hospital admission – 15 days vs. 21 days in patients operated on later (p < 0.001) [27].

Also in correlation with the previous study are the results of the study carried out by Lefaivre et al., wherein it was proven that waiting for an operation for longer than 48 h represented a significantly greater risk for the development of serious medical complications and the lengthening of hospital stay [26].

 In their systematic review paper, which included 52 studies and 291,413 patients, Khan et al. identified 25 studies which also took into consideration the length of hospital stay. They concluded that there was significant correlation between earlier surgical treatment and shorter hospital stay [18].

Analysis of available literature determined that the lack of an available operating theatre and the lack of staff were being stated amongst the main factors responsible for delaying surgical treatment [28]. By resolving nonmedical reasons for delaying surgical treatment, we can expect an improvement in treatment outcomes.

EARLY FUNCTIONAL RECOVERY

 Early rehabilitation and verticalization of patients also mean earlier functional recovery and quicker regaining of independence [29].

Oldmeadow et al. showed that earlier rehabilitation in surgically treated patients with hip fracture was linked to earlier discharge from hospital, and that it accelerated functional recovery [30].

In their study, Kohn et al. showed that patients who were operated on longer than 48 h after hospital admission had poorer functional recovery [29].

Bearing in mind that the aim of surgical treatment of hip fracture is pain elimination for the patient, appropriate hip joint reconstruction, depending on the type of fracture, and ultimately the return of the patient to the full level of activity that they had prior to hip fracture, functional recovery remains one of the most important goals of treatment in these patients. It is necessary to carry out additional studies that would identify all factors affecting how quickly and successfully adequate results are achieved, which would be important determinants in forming guidelines for treating patients with hip fracture.

CONCLUSION

 Patients with hip fracture should be operated on within 24 h of hospital admission, unless there is an acute medical condition that is preventing the surgery. If there is a medical condition which can be remedied, the threshold is raised to 48 h, but the waiting period should not be longer than 4 days.

Nonmedical reasons for delaying surgery should also be taken into consideration, and efforts should be made to minimize their effect on surgical treatment planning.

A multidisciplinary approach (orthopedic surgeon, anesthesiologist, appropriate specialists) should provide for the realization of the surgery within the first 48 h or, exceptionally, within the first 4 days of admission, in order to minimize the risk of the development of complications as well as reduce the increase in already high mortality, in the first 30 days and the first year after surgical treatment.