A Decision Support System for the Surgical Care during the Epidemic of Covid-19

Abstract

Faced with the Covid epidemic, the optimization of human resources and materials is necessary to be able to treat as many victims as possible and to save them so as much as possible. Schedules are usually faced with a situation where new measures related to Covid are considered. This leads to higher risks and complications, especially in the preoperative service. Adapt the organization’s surgical department for preserving their capacity and taking care of Covid and not Covid patients. To the best of our knowledge, the existing studies in the literature have treated the Covid scheduling task only on a service of the surgical process, mostly the preoperative service. In this study, we aim to design the keys of a new organization to preserve hospitalization capacities and ensure continuity of care, including all services of the surgery.

1. Introduction

The number of disasters has increased in recent decades in significant proportions. These disasters often result in a significant number of casualties requiring an urgent response. Faced with such a situation as the epidemic Covid, conventional and routine health means are often overtaken, and therefore is not effective to minimize this massive influx of victims.

The country has faced a new virus known as Corona Virus Disease 19 or Covid-19. Covid-19 spreads very quickly from person to person by contact. Covid-19 has resulted in our hospitals, and healthcare system is saturated by the number of critically ill people.

Hospitals are the mainstay of the care of severe Covid-19 patients; resuscitation service of the hugest hospitals have dozens of beds dedicated to the care of patients with Covid 19. Thus, the implementation of a system of hospital management conditioned by an optimization of the various medical resources is essential for patient safety. All actors in health facilities must be ready to face the health crisis generated by Covid-19.

Limiting the impact of Covid-19 care on scheduled and emergent activities must prevail during the rebound phase. The emergent cases must be limited as much as possible. The equity of access must be guaranteed to all patients. Thus, the burden related to Covid-19 must be shared equitably between the different territories and establishments. This principle should guide cooperation territorial and regional solidarity so as not to saturate a territory or an establishment and avoid inaccessibility to non-Covid care in these territories. The principle of territoriality of the adaptation of the hospital care must be driving the hospital response. Thus, within each territory, a declination operational regional principle must be carried out between hospital actors.

At the same time, they continue their indispensable activity for the care of the population. The particularity of the hospital system in exceptional situations is that it bases on the one hand on the emergency requiring decisions to be taken and quick actions to be carried out and, on the other hand, on the large number of victims to be treated in a short time. There is a lot of work that deals with organizational and optimization problems in hospital systems in normal circumstances. They are usually based on methods and tools from the manufacturing sector [1]. Most of this work is interested in the optimization of the operating room, which represents a bottleneck resource in the hospital system.

In the complex hospital, some departments have a lack of beds that will affect the quality of care, especially in the operating theater as the most sensitive department. Since the beginning of the crisis, there has been a lot of interest in the technical elements of patient care such as the positioning of patients in the supine position, artificial coma, but the functional and organizational changes are also very important.

To give all professionals, whether doctors or caregivers, the keys to a new organization to preserve hospitalization capacities and ensure continuity of care by:

• Strengthening as much as possible the upstream of the hospital sector as well as its alternatives to avoid any unnecessary hospitalization;

• Streamlining the path of hospitalized patients between conventional or scheduled stays, critical care (and no longer only in intensive care), and follow-up and rehabilitation care.

  Units resuscitation made up of structures perennial, ephemeral, or upgraded, taking in charge of patients the most severe (intubation, failure extra-respiratory…).

Intensive care service (Covid IC) consists of the structures of critical care outside resuscitation, welcoming Covid patients less severe (management noninvasive, mono defiance respiratory,…).

Cooperation is encouraged between professionals (hospital and researchers) to ensure rehabilitation patients downstream of critical care, prevent and manage the post-resuscitation organization. Patients who have gone through the acute phase of the disease can be transferred to Covid IC, downstream of resuscitation. These health disasters of different natures and durations have resulted from the need to have a specific organization for service.

The care of Covid-19 patients has generated many changes in the organization of surgical services. In this chapter, we will study the impact of Covid on surgical care in the literature and design a complete decision support system for ensuring the continuity of surgical care during the epidemic of Covid-19.

2. Literature review

In this section, we will present the recent studies that proposed some solutions to manage the surgical cases in the Covid period. We will present the most recent studies in different surgery specialties: urologic, aortic, otorhinolaryngology and head and neck surgery, orthopedic, gynecologic, endocrine, maxillofacial, neurosurgical, and vascular service.

Tejido-Sánchez et al. [2] have modeled a care protocol to restart scheduled surgical activity in a Urology service of a third-level hospital in the Community of Madrid, in a safe way for the patients and professionals in the context of the Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2) epidemic. They have tested their protocol on 19 patients, 19 patients have been scheduled, of which two have been suspended for presenting Covid-19, one diagnosed by positive PCR for SARS-CoV-2, and another by laboratory and imaging findings compatible with this infection. No complications related to Covid-19 were detected after 10 days. That indicates that their proposed protocol ensures the correct application of preventive measures against the transmission of coronavirus infection is being safe and effective.

Covid-19.

To measure the impact of the delay of the programmed aortic surgeries during this epidemic, Perera et al. [3] have demonstrated that the death of 4.7% of postponed patients. Kail et al. [4] have discussed medical precautions required in the clinic, inpatient ward, and operation room of the otorhinolaryngology head and neck department, which aims to protect healthcare workers from Covid-19. While Sun et al. [5] have aimed to improve the success rate of treatment for otorhinolaryngology, head and neck surgery emergency surgeries and to reduce the SARS-CoV-2 infection rate in the perioperative period.

For the same objective of [3], M. Durand et al. [6] have dealt with the Covid conditions that allow the reporting of operations in the head and neck department. An analysis of reported patients is integrated into their studies.

In the orthopedic surgery department, Singh et al. [7] have determined the safety of elective, outpatient orthopedic sports procedures during the coronavirus pandemic at a high-volume orthopedic practice.

Piketty et al. [8] have focused on the new transformations generated by the Covid in the gynecologic department in the Foch hospital located in Paris, France. The authors have evaluated the surgery delays and their impacts on patients.

Kho et al. [9] have determined the incidence of perioperative coronavirus.

Disease in women undergoing benign gynecologic surgery and to evaluate perioperative complication rates in patients with active, previous, or no previous severe acute respiratory syndrome coronavirus 2 infections. Ozoner et al. [10] have proposed a comprehensive guide using existing guides and recommendations for reorganizing daily practice and the academic routine of neurosurgery during the Covid-19 pandemic. This study also aims to refine the substantial information for neurosurgical practice about this pandemic disease. Ermer et al. [11] have tracked endocrine surgery patients with treatment delays due to Covid-19 to investigate the relationship between Physician Assigned Priority Scoring (PAPS), the Medically Necessary, Time Sensitive (MeNTS) scoring system, and delay to surgery. Pagotto et al. [12] have evaluated the possible impacts of Covid-19 on oral and maxillofacial surgery practice, as well as the protocols employed by oral and maxillofacial surgeons to minimize the risks of contamination.

Also, Asghar [13] has considered indicators such as the presence of symptoms, characteristics of patients (age, sex,…), and hospital data to study the results of the SARS test for oral-maxillofacial operations in 2020.

Among the addressed problems of the surgical department, the scheduling problem is a fundamental interest for the researchers because the scheduling task has a key role especially for the department having expensive resources. Thomson et al. [14] have cited several studies that approve the efficiency of hypo fractionated radiotherapy. They have evaluated the Covid changes on the surgery schedules to design a future complete database.

Güler et al. [15] have addressed the physician scheduling problem of a hospital during a Covid-19 pandemic. They have developed a Mixed-Integer Programming (MIP) model and embedded it into a spreadsheet-based Decision Support System (DSS).

In efforts to ensure adequate healthcare resource utilization, many electives or nonemergent surgical cases have been canceled since the coronavirus disease 2019 began, Dorash et al. [16] have analyzed the impact of the Covid-19 pandemic on surgical delays and adverse outcomes for patients with venous disease scheduled to undergo elective operations.

To the best of my knowledge, there is no quantitative study in the literature that considers the Covid policies in the whole surgical process. Authors are limited on one stage of the surgical process, as in [9], they have determined the incidence of perioperative coronavirus disease in women undergoing benign gynecologic surgery and to evaluate perioperative complication rates in patients with active, previous, or no previous severe acute respiratory syndrome coronavirus 2 infections.

Truche et al. [17] have quantified the surgical backlog during the Covid-19 pandemic in the Brazilian public health system and determined the relationship between state-level policy response and the degree of state-level delays in public surgical care.

Özkan et al. [18] have proposed a multicriteria optimization model while considering Intensive care unit admission for Covid-19-positive patients. The authors have used different methods to prioritize both criteria and patients, the Fuzzy Analytic Hierarchy Process (AHP) method to prioritize 19 criteria, and MULTIMOORA (Multi-Objective Optimization Based on a Ratio Analysis) is used to rank Covid-19-positive patients. They aim to find out which patient is more urgent for the intensive care unit.

Despite the added values of this research cited to optimize the scheduling tasks of surgical processes in the Covid period remains unresolved. it comes down to the continuous evolution of the epidemic and also to the complexity of the problem. In this study, we aim to design a global scheduling model of surgical processes in the Covid period while citing the different additional constraints compared with the traditional surgical process model.

3. COVID-19 operating room patient scheduling

3.1 Problem statement

We are considering the surgery scheduling problem whose objective is to assign an operating room and a one-day time slot to each programmed surgery. The operative process is triggered when a patient takes the appointment of surgical consultation and proceeds until exiting the hospital. This period is known in the scheduling theory as flow time. It breaks down into three-time services: the preoperative service, the per-operative service, and the postoperative service. The preoperative service corresponds to caring for patients until the day before surgery. The per-operative service is characterized by the duration of the surgery. The postoperative service covers all the care received by the patient after the surgery. In the preoperative service, the required resources are nurses, Pre-Holding (PH) beds while nurses and Post-Anesthesia Care (PAC)/Intensive Care Unit (IC) beds are involved in the postoperative service.

3.2 Perioperative management of surgical procedures during the Covid-19 pandemic

During Covid-19, new security and prevention measures are integrated into all stages of the surgical process, the operating rooms, and its facilities. Among these measures, a Covid test is required within three days of the operation date. This measure is applied to inpatients and outpatients, even if the patients do not have the Covid symptoms.

For patients who have a negative Covid test, their surgeries cannot be postponed and will be performed under prevention tools such as mask, spacing, respiratory protection, and reducing the access number to the OR and the staff exposure. For optimal use of human and material resources, operations can be grouped. Standard perioperative rules and transport procedures will have to be respected.

The consideration of the patient priority and urgency should be among the priorities of Covid surgical management.

3.2.1 Decision-making elements for performing surgery

Decisions to offer surgical treatment to the patient are made to ensure the absence of loss of chance in the treatment of each patient. Over-morbidity potential related to Covid-19 postoperative is part of the decision elements The order of programming is also taken in a multidisciplinary way, such as usually. This prioritization takes into account, among other things, the recommendations of up-to-date and available good practices, discussion with patients, impact on the patient’s life expectancy or quality of life, the pathology involved, the context epidemic, and of course the possibilities of each surgeon (vacation). When the structure is not able to implement in the interest of the patient, surgical management within a time frame adapted to his situation must be considered to refer the patient to a structure able to ensure this care, thus allowing respect of the principle of access to care. To avoid any additional delays during these transfers of care, the structures are invited to organize themselves at the level territorial to prepare the management of this type of situation.

3.2.2 Proposals from surgical disciplines

Most disciplines have proposed a classification into four categories:

• Level 1: urgent care

• Level 2: coverage with the potential loss of chance if the postponement is greater than two or three months.

• Level 3: coverage with the potential loss of opportunity if the postponement of intervention is more than 6 months.

• Level 4: nonurgent care. Potential loss of opportunity if the postponement is more than 1 year

However, this classification may have justified postponing certain interventions by one month. Especially in oncology at the beginning of the white plan period. This means that these interventions can become priorities. The management of these patients can be carried out in another establishment if the blocks are not free at the level of the initial establishment.

In the current situation, the objective is to continue or even improve access to the management of surgical emergencies and “semi-emergencies,” in proximity and at the level of the premises.

3.2.3 Conditions of support

1. A. Structures and premises:

In the current phase of the plateau of the epidemic and then that of degrowth, it will be necessary beforehand to determine at the regional and territorial level the volume of places resuscitation and beds or even Covid + blocks to keep. The reduction of the need for resuscitation beds will make it possible to regain conditions classic for surgical management in non-Covid units.

1. B. Situations:

   • Outpatient care with the circuit in a UCA (Surgical Unit Ambulatory) to prioritize

   • Conventional management with postoperative monitoring in PACU then in hospitalization (in room only in non-Covid units)

   • Conventional management with postoperative monitoring in PACU then in intensive care and finally in hospitalization (in a room alone in the non-Covid units)

   • Given the still partial knowledge about this epidemic, it is recommended to set up differentiated sectors (Covid and non-Covid) at the level of most institutions, while maintaining protective measures for caregivers and patients in all units.

1. C. Patients

They are informed by the surgeon and the anesthetist of the special conditions related to the Covid-19 pandemic, including the assessment of the risk/benefit balance of the intervention and the epidemic context at the time of the date of its intervention. The tracing in the patient’s file of this information is essential.

They are also informed of symptoms suggestive of Covid-19 justifying contact with the surgical team and being able to postpone the surgical intervention.

Systematic contact the day before the intervention would be desirable with the same objective: determine a date of intervention and a place of care: specific Covid sector.

Screening for SARS-CoV-2 by RT-PCR of asymptomatic patients may be offered within 24/48 hours in preoperative, in case of:

• comorbidity at risk of a severe form of Covid-19,

• contact with a confirmed Covid-19 patient in the last 7 days,

• aerosol-generating surgeries,

• so-called major surgeries, at risk of severe form postoperatively (e.g., surgery),

• cardiac, abdominal, and heavy pelvic, organ transplantation, etc.).

Saliva samples may be more sensitive.

• In the case of positive sampling, the intervention will be postponed if possible, by 10 days.

• In the event of a confirmed intervention, with a positive sample, it is desirable to carry it out in a Covid+ sector.

• In case of emergency intervention, if the result of the sampling is not available, it is desirable to carry it out in a Covid+ sector.

Serological tests can be performed as soon as validated, and then certified tests are obtained by the competent authorities and integrated into care strategies. Computed Tomography (CT) scan of the chest can also be integrated into a strategy for analyzing the risk of contamination, particularly in case of emergency.

However, in adults, in the absence of availability of rapid biological testing, the performing a chest scan for lung damage silent in patients of unknown Covid status may be admissible in case emergencies (not allowing to wait for the results of the PCR) for another pathology, such as “Emergency surgical interventions, (ENT, oncology, etc.),…”

1. D. Healthcare professionals

A serological test could be performed as soon as validated tests are obtained and then certified by the competent authorities and integrated into the arrangements for the assignment of staff, by the function of recommendations.

In the absence of immunization or the current period (pending validation of tests serological), a nasopharyngeal swab is performed for personnel symptomatic or contacts at risk, a nasopharyngeal swab is performed for personnel symptomatic or contacts at risk. If the sample is positive, an isolation measure is taken following national recommendations.

Pending the availability of all validated and certified biological tests, the instructions regarding the personal protective equipment of caregivers remain unchanged.

3.3 Constraints

The OR scheduling problem treated in this study includes all the services of the surgical process. Our model includes the most constraints in the real-life operating room department. Additional constraints related to the Covid policies will be presented also.

We assume various realistic procedures:

• In the surgical process, the patient flow includes three services without waiting time between them

• A unit service cannot be interrupted before its end

• Same priority for all patients

• The operating rooms are uniforms

• There is no ordering constraint between services of different operations

• The duration of each service is a deterministic parameter

• The transfer time between the services of an operation is determined under Covid policies

• The setup time is considerable under Covid policies

The following constraints are considered in the optimization model:

No-wait in the surgical process: The operating theater includes beds in PH service, operating rooms, and beds in PAC or IC services. Each patient must first pass through a bed of PH service and then into an operating room and then through a bed of PAC/IC services without waiting time between these three units.

Resources type: The resources of operating theater are classified into several types according to the resources required by the operation.

Operation type: Three types of operation: small, large, and extra-large, this classification depends on the length of the operation duration. The operating times for each service were defined as follows: the duration of the preoperative service is fixed for all operations, and similarly the duration of the postoperative service is fixed for all operations. The duration of the preoperative service is different on the operation type.

Requirement compatibility of operation and operation specialty: we have considered several operation specialties in the model and consequently different surgeon specialties are presented.

Availability of surgeons: Ensure the availability of the assigned surgeon.

Resource number: The number of resources required on resource type C must exactly be equal to the assigned resources to perform the surgery i in the service j.

In our model, we consider the followings sets, parameters, and decisions variables.

$I$: All operations, $i=1..N$.

${\mathit{JO}}_i$: All services of operation$i$, ${\mathit{JO}}_i=\left\{1,2,3\right\}$, $i=1..N$.

$P$: All operation specialties, $p\in P$.

$C$: 0peration complexity$c$, $C$= {1: difficult; 2: easy}, $c\in C$.

$S$: Elements of resources. $s$= {professor surgeon, resident surgeon, assistant surgeon, anesthesiologist, nurse, anesthetist, OR, PH bed, and PAC bed}.

${\mathit{JR}}_s$: operation services that can be treated by resource$s$, $s\in S$.

$n_{\mathit{ij}}^s$: The required resource s for treating operation$i$ at service $j$. $i\in I$, $j$= 1, 2, 3, $s\in S$.

$T_{\mathit{ij}}^s$: The duration of operation $i$ at service $j$ by resource$s$. $i\in I$, $j$= 1, 2, 3, $s\in S$.

${\mathit{TW}}_S^t$: The availability of resource $s$. ${\mathit{TW}}_S^t=\left[{\mathit{STW}}_S^t,{\mathit{ETW}}_s^t\right]$where ${\mathit{STW}}_S^t$ and ${\mathit{ETW}}_s^t$are consecutively the start time and the end time of the time window $t$, $t\in N$, $t\le \mid {\mathit{TW}}_s\mid$.

$M$: A large positive number.

${\mathit{RT}}_1$: Working time of doctors.

${\mathit{RT}}_2$: Working time of anesthetists and nurses.

$R_{\mathit{ij}}^s$: The availability of resource $s$ during service $j$ of operation$i$. $R_{\mathit{ij}}^s$= 1 if the resource $s$ is available, $R_{\mathit{ij}}^s$= 0 otherwise. $i\in I$, $j$= 1, 2, 3, $s\in S$.

$B_{\mathit{pc}}^i$: =1 if an operation $i$ is suitable to specialty $p$ and complexity$c$, $B_{\mathit{pc}}^i$=0 otherwise, $i\in I$;$p\in P$.

$Q_{\mathit{pc}}^s$: =1 if a resource$s$ can treat the operation in its specialty $p$and complexity $c$, $Q_{\mathit{pc}}^s$=0 otherwise. $s\in S$.

${\mathit{ST}}_{\mathit{ij}}$: Beginning of operation$i$,$i\in I$, $j$= 1, 2, 3.

${\mathit{CT}}_{\mathit{ij}}$: End of operation $i$ at service $j$,$i\in I$, $j$= 1, 2, 3, $s\in S$.

$X_{\mathit{ij}}^s$: =1 if resource $s$ is assigned to operation $i$ at service $j$, $X_{\mathit{ij}}^s$=0 otherwise, $i\in I$, $j$= 1, 2, 3; $s\in S$.

$A_{\mathit{aa}\text{'}}$: =1 if operation stage $a$ occurs before operation stage $a\text{'}$ requiring the same resource, $A_{\mathit{aa}\text{'}}$= 0 otherwise, $a,a\text{'}\in J_s$.

$y_{\mathit{aa}\text{'}}^i$: For the same operation$i$, $y_{\mathit{aa}\text{'}}^i$=1 if its service $a$ precedes service $a\text{'}$, $y_{\mathit{aa}\text{'}}^i$=0 otherwise. $\mathrm{a},\mathrm{a}\text{'}\in {\mathrm{J}}_{\mathrm{i}}$, $i\in I$.

$v_{\mathit{ij}}^{\mathit{st}}$: =1 if resource $s$ performs operation $i$ at service $j$ within its available time window${\mathit{TW}}_s^t$,$v_{\mathit{ij}}^{\mathit{st}}$ =0 otherwise. $i\in I$, $j$= 1, 2, 3; $s\in S$; $t\in \left[1,|{\mathit{TW}}_s|\right]$

$${\mathit{CT}}_{\mathit{ij}}={\mathit{ST}}_{\mathit{ij}}+{max}_{s\in S}\left\{T_{\mathit{ij}}^s.X_{\mathit{ij}}^s\right\};i\in I,j=1,2,3$$E1

$${\mathit{CT}}_{\mathit{ij}}={\mathit{ST}}_{i\left(j+1\right)},i\in I;j=1,2$$E2

$${\mathit{CT}}_{\mathit{ia}\text{'}}-{\mathit{CT}}_{\mathit{ia}}\ge {max}_{s\in S}{T}_{\mathit{ia}\text{'}}^s-M\left(1-y_{\mathit{aa}\text{'}}^i\right),a<a\text{'};i\in I;a,a\text{'}\in {\mathit{JO}}_i$$E3

$${\mathit{CT}}_{\mathit{ia}}-{\mathit{CT}}_{\mathit{ia}\text{'}}\ge {max}_{s\in S}{T}_{\mathit{ia}}^s-M{y}_{\mathit{aa}\text{'}}^i),i\in I;a,a\text{'}\in {\mathit{JO}}_i;a<a\text{'}$$E4

$${\mathit{CT}}_{i\text{'}a\text{'}}-{\mathit{CT}}_{\mathit{ia}}\ge {max}_{s\in S}{T}_{i\text{'}a\text{'}}^s-M\left(1-A_{\mathit{aa}\text{'}}\right);i,i\text{'}\in I,i\ne i\text{'};a,a\text{'}\in {\mathit{JR}}_s$$E5

$${\mathit{CT}}_{\mathit{ia}}-{\mathit{CT}}_{i\text{'}a\text{'}}\ge {max}_{s\in S}{T}_{\mathit{ia}}^s-M{A}_{\mathit{aa}\text{'}};i,i\text{'}\in I,i\ne i\text{'};a,a\text{'}\in {\mathit{JR}}_s$$E6

$$\sum _{s\in S}{X}_{\mathit{ij}}^s.R_{\mathit{ij}}^s=n_{\mathit{ij}}^s;i\in I,j=1,2,3$$E7

$$\sum _{c\in C}\sum _{p\in P}{B}_{\mathit{pc}}^i.Q_{\mathit{pc}}^s\ge X_{\mathit{ij}}^s;i\in I,j=1,2,3;s\in S\cap \left\{1,2,3\right\}$$E8

$$X_{\mathit{ij}}^s.\sum _{t=1}^{\mid {\mathit{TW}}_s\mid }\left(v_{\mathit{ij}}^{\mathit{st}}.{\mathit{STW}}_s^t\right)\le {\mathit{ST}}_{\mathit{ij}};i\in I,j=1,2,3;s\in S$$E9

$$X_{\mathit{ij}}^s.\sum _{t=1}^{\mid \mathit{TWs}\mid }\left(v_{\mathit{ij}}^{\mathit{st}}.{\mathit{ETW}}_s^t\right)\ge C{T}_{\mathit{ij}}^s;i\in I,j=1,2,3;s\in S$$E10

$${\mathit{ST}}_{i1}\ge 0,i\in I$$E11

$$\sum _{s\in S}{X}_{\mathit{ij}}^s=1;i\in I,j=1,2,3$$E12

$$X_{\mathit{ij}}^s\in \left\{0,1\right\}i\in I,j=1,2,3;s\in S$$E13

$$y_{\mathit{aa}\text{'}}^i\in \left\{0,1\right\}i\in I;a,a\text{'}\in {\mathit{JO}}_i$$E14

$$A_{\mathit{aa}\text{'}}\in \left\{0,1\right\}a,a\text{'}\in {\mathit{JR}}_s$$E15

Equation (1) calculates the end time of operation $i$at service j. Equation (2) defines that the end of operation i at service j is the beginning of stage j + 1 of operation i (no-wait). Equations (3) and (4) indicate that two services of an operation i should not be treated at the same time. Equations (5) and (6) determine that a resource s can be only assigned to one operation service simultaneously. Equation (7) means that the assigned resource should conform to the necessary resources to operate i at service j. Equation (8) means that the assigned surgeon has the required proficiency required by the operation specialty and complexity. Equations (9) and (10) mean that the operation must be performed during the available time windows of its assigned resources. Equation (11) means that all operations beginning equal to or superior to time 0. Equation (12) indicates that an operation must be treated once only. Equations (13) to (1) are binary variables.

To obtain a Covid optimization model that includes all the services of the surgical process and all specialties, the following constraints are added in the optimization model:

• No surgeries were performed without PCR results

• Only patients with negative test results were operated on

• Patients with positive signs were canceled and asked to come for a PCR test. Singh et al. [7] have approved that 3.5% of patients tested positive for Covid-19 and were significantly younger when compared with patients testing negative. As of April 3, all scheduled patients received a PCR test in the hospital on the eve of surgery.

• Patients whose operation was postponed were contacted by the department secretaries and physicians during the 4 months following the study period. After five unsuccessful calls, patients were deemed lost to follow-up.

• Management of asymptomatic or confirmed Covid-19+ patient. If possible, it is best to postpone the intervention 7–10 days after the end of symptoms.

• Preference should be given to an outpatient intervention.

• The need for a large quantity of special equipment to ensure personal protection such as masks, gels,… these products are very necessary for the healthcare providers especially in the most affected areas by Covid-19. Unfortunately, they are not always available with the necessary quantities.

• Healthcare staff must do the necessary precautions to protect against the transmission of Covid-19 from patients.

• Patients who are attracted by Covid-19 were usually hospitalized and needed the care of healthcare workers.

• The Covid patients are more prior than the elective patients to use the ORs that integrate breathing machines.

• For safety, and to ensure that resources, hospital beds, and equipment are available to patients critically ill with Covid-19, non-emergency procedures be delayed. Factors will influence whether the operation should be done now or delayed. They will include the extent of Covid-19 including the hospital’s capacity.

4. Conclusions

As pandemic Covid-19 dynamically changes in our society, it is important to consider how the pandemic has affected the schedules of surgical operations. To develop a complete surgical scheduling model integrating Covid policies, we aim to identify additional constraints in all stages of the surgical process that could be used to inform practice and policy for future pandemics and disasters. This study could be the pioneer for global optimization of surgical service during the epidemic. This search provides for the initiation of several specific procedures on the part of the nursing and administrative staff with a minimum of modification of the traditional hospital organization. But these forecasts must be adapted to cultural conditions and specific economic means. This search can be considered the pioneer of future optimization models that consider the complete Covid surgical process. Organizations continue to prepare recommendations for physicians treating patients including those with cancer. The physicians treating you are meeting in teams to guide ongoing care. Care options may include other treatments while waiting for a safe time to proceed with surgery.