Preloaded vs manually loaded IOL delivery systems in cataract surgery in the largest ambulatory surgery center of northwestern China: an efficiency analysis

With the development of surgical instruments and surgical skills, cataracts can be easily, safely and cost-efficiently treated with a routine operation [1, 2]. However, cataracts remain the second leading cause of visual impairment and the leading cause of vision loss throughout the world [3‐5]. A recent study showed that, in 2010, cataracts resulted in 94 million people being visually impaired and 20 million blind [6]. By 2020, more than 30 million people are predicted to undergo cataract surgery annually worldwide [7].

As the population ages, the prevalence of cataracts is expected to increase correspondingly. In China, among people aged 45–89 years old, the number of cataract cases was 50.75 million in 1990 and 111.74 million in 2015 [3]. By 2050, it is predicted that 240.83 million people aged 45–89 years old will be affected by cataracts [3]. The doubling of cataract patients and the delay in cataract surgeries pose challenges for limited healthcare resources and governments. More efficient and effective surgical techniques are needed to provide reliable outcomes and to improve cataract throughput.

In standard cataract surgery, the opacified lens is phacoemulsified, and an artificial foldable intraocular lens (IOL) is inserted through a small incision [8, 9]. The IOL is manually folded using forceps and is inserted into an injector system. Loading of the IOL requires more extended time for the overall surgery and longer training for the operating staff, which is time-consuming because of the differences in the designs of the manual injection systems from various companies. Furthermore, manual loading of the IOL increases the risk of damage to it, as well as surgeon error in holding and folding of the IOL [10, 11]. To address these concerns, preloaded IOLs (P-IOLs) have been developed, holding the potential to reduce IOL loading errors, eliminate additional handling of IOLs, decrease total case time, and improve throughput [10, 11].

To evaluate the efficiency of P-IOL vs manually loaded IOL (M-IOLs) delivery systems in cataract surgery, a prospective, observational study was conducted. We compared the surgery time between the P-IOL and M-IOL delivery systems in one- and two-operating room scenario. Using the efficiency and revenue implications of introducing a preloaded delivery system for IOLs in cataract surgery systems, we further estimated the potential throughput and hospital revenue using P-IOL without more staff.

In the present study, all of the cataract surgeries were performed by one experienced surgeon. Before starting the study, the P-IOL system (TECNIS iTec Preloaded Delivery System) had been adopted in our hospital for more than 2 years. Thus, the surgeon was familiar with both preloaded IOL and M-IOL delivery systems. A total of 200 routine cataract cases were enrolled in the study, of which 98 were performed with P-IOL, and 102 were performed with M-IOL. Details of the study population can be seen in Table 1.

Time and motion data are shown in Tables 2 and 3, respectively. In the 1-OR scenario (Table 2), the setup time, lens time and tear down time were significantly reduced using P-IOL compared with M-IOL (P < 0.01). There was a reduction trend in surgery time using P-IOL (− 6.8% vs M-IOL, P > 0.05), but it did not reach statistical significance. The mean total case time was 16.9 min using P-IOL, which was a 7.7% reduction (1.1 min per case) compared with M-IOL (P < 0.05). In the 2-OR scenario (Table 3), the mean total surgeon time was 10.8 min using P-IOL, which was a 7.8% reduction (0.9 min per case) compared with M-IOL (P < 0.05).

To estimate the change in cataracts throughput and hospital revenue from switching from the M-IOL delivery system to the P-IOL system, efficiency and revenue implications of introducing a preloaded delivery system for IOLs in cataract surgery model were used (as shown Figs. 1 and 2, respectively). In 2019, 18,635 routine cataract surgeries were performed (77.6 per surgery day) in our ambulatory surgery centers, with 97.0% being monofocal IOL insertions. Assuming that the center runs as four independent 1-OR scenarios, 4 more operations will be performed per surgery day (Table 4). The annual throughput will increase by 5.2% (960 cases), accompanied by an increase in revenue by 284,352 USD (Table 5). Assuming that the center runs as 2 independent 2-OR scenarios, 6 more operations will be performed per surgery day (Table 4). The annual throughput will increase by 7.7% (1440 cases), accompanied by an increase in revenue by 426,528 USD (Table 5).

With the accelerated aging of the population, the increasing number of cataract patients and delays in cataract surgery pose challenges for limited healthcare resources and governments. Thus, more efficient and effective surgical techniques are needed to provide reliable outcomes and improve cataract throughput. In the present study, we compared the efficiency of P-IOL vs M-IOL in our ambulatory surgery center. We found that application of the P-IOL significantly reduced the total surgery time both in the 1-OR and 2-OR scenarios. Using our designed model, it was estimated that the switch from M-IOL to P-IOL could increase the throughput by 5.2–7.7% and increase the revenue by 284,352 to 426,528 USD without additional staffing and operating rooms.

Years ago, nearly all cataract surgeries required inpatient hospitalization. Recently, an increasing number of cataract surgeries have been performed at ambulatory surgery centers in China, improving cataract throughput and convenience for patients and surgeons. In addition, performing cataract surgeries at ambulatory surgery centers enhances surgeon productivity, decreasing out-of-pocket patient costs, and per-case costs for insurers [12]. In 2015, an ambulatory surgery center was established in our hospital to perform routine cataract surgeries, substantially improving cataract throughput. With the acceleration of aging of the population in China and worldwide, the cataract patients will double in 30 years, posing challenges for healthcare systems and limited healthcare resources. For routine cataract surgery, the average surgery time is as short as 10–20 min. Therefore, even small changes in the efficiencies of operating processes and surgical techniques can quickly add to meaningful differences in cataract throughput and efficiency of the healthcare system.

To provide better operating conditions, P-IOL delivery systems were developed. The perceived benefits of P-IOL delivery systems include the elimination of IOL injector loading variability, avoidance of potential IOL loading errors, lower risk for instrument contamination and reduced operation time [10, 11, 13‐15]. In this study, our data showed that, in a 1-OR scenario, application of the P-IOL system reduced the average total case time by 1.3 min (− 7.7%) relative to the M-IOL system. The reduction of the total case time was largely the result of the reductions in operating setup time, tear down time, surgery time and IOL delivery time. The reductions in operating setup time might be ascribed to that the injector in the M-IOL group is reusable, and more time is needed to confirm the sterilization of the injector, open the sterilized package and check whether the injector is normal. In a 2-OR scenario, application of the P-IOL system reduced average total case time by 0.9 min (− 7.8%) relative to the M-IOL system. The reduction of the total case time was the result of the reductions in surgery time and IOL delivery time, rather than surgery delay time. This outcome was somewhat different from previous findings that the reduction of surgery delay time also contributed to the reduction of total cases [10], which might be ascribed to the staff structure optimization in our institution, according to which a circulating nurse and a resident were in one operating room. Thus, they cooperated well and had sufficient time to prepare the surgery equipment and patients.

The staff and operating room are both valuable and expensive. Maximization of staff and operation room efficiency could provide medical serves to more patients. In this study, the efficiency and revenue implications of introducing a preloaded delivery system for an IOL model were used to evaluate the changes in cataract throughput and hospital revenue from switching from the M-IOL delivery system to the P-IOL system. Within a 1-OR center, if the total case time savings per surgery day exceeds the mean time between the start of the operating setup time and the completion of the operating’s tear down with the preloaded system, then an additional case, or cases, can be added to the surgery day without additional staffing. In a 2-OR center, if the total surgeon time savings per surgery day exceeds the total surgery time with the preloaded system, then an additional case, or cases, can be added to the surgery day without additional staffing. Thus, by switching from the M-IOL system to the P-IOL system, annual throughput will increase by 5.2% (960 cases) in the 1-OR scenario and 7.7% (1440 cases) in the 2-OR scenario. Similarly, Jones, et al. reported that, in a single-OR cataract surgery center in Canada, the cataract throughput increased by 9.9% (36 cases per year) by switching from the M-IOL system to the P-IOL system without increasing staff or surgeon capacity. In 2-OR cataract surgery centers (France and the USA), the cataract throughput will increase by 5.7% (90 per year in France) and 4.0% (96 per year in the USA), respectively.

The cost of cataract surgery per case varies widely depending on location and setting in which the surgery is performed. A study of nine European countries showed that the cost of cataract surgery per case ranged from 344 to 1177 USD. In our ambulatory surgery center, the average cost of cataract surgery is 296.2 USD, which means 296.2 USD of revenue for the hospital. Switching from the M-IOL delivery system to the P-IOL system, the hospital could increase its revenue by 284,352 USD in the 1-OR scenario and 426,528 USD in the 2-OR scenario. In contrast, for hospitals like our ambulatory surgery center, for which the salaries for the surgeon and staff depend on the throughput, translating from the M-IOL delivery system to the preloaded system could potentially increase the input of the surgeons and staff.

Although the findings are promising, the current study had several limitations. First, the present study was limited by the data collection being performed at a single ambulatory surgery center by a single observer over a short period of time, thereby limiting the generalizability of the findings. Second, in the present study, the surgeon loaded the M-IOL himself, while in hospitals in which the staff helps to load the M-IOL, the surgery time is expected to be further reduced. Third, for feasibility reasons, only one type of IOL was compared in this study. In the future, a more detailed record of the different types of IOL from various manufactories would provide better data for decision making. Fourth, the present study focused on the influence on cataract throughput and revenue by the application of P-IOL, and we did not specifically track patient outcomes before and after implementation of P-IOL or M-IOL. The surgeon did not anecdotally note evidence of increased intraoperative or postoperative complications.

This report is the first of a comparison of two IOL delivery systems in China using different settings of the scenario. Our study showed that using the P-IOL delivery system for routine cataract surgeries reduces total case time relative to the M-IOL delivery system in both the 1-OR scenario and 2-OR scenarios. The P-IOL delivery system has the potential to increase cataract throughput and revenue. This outcome is of interest in a healthcare environment that is increasingly focused on improving efficiency and time savings. The application of P-IOL could help to increase the efficiency of the healthcare system and reduce the burden, dramatically increasing the number of cataract patients.