Describe, in short, how OR process was improved and how this improvement affected the process metrics (flow time, value added time, waste and % value added time)

Describe, in short, how OR process was improved and how this improvement affected the process metrics (flow time, value added time, waste and % value added time)

 

management calcuations
Project instructions:
please read the paper the paper attached and answer the following:

1. For the high level value stream map in figure 1, calculate the following
a) Flow time
b) Value added time
c) Waste
d) Percent value added time , given that % value added time =
Value added time / Flow time

2. Describe, in short, how OR process was improved and how this improvement affected the process metrics (flow time, value added time, waste and % value added time)

Langenbecks Arch Surg (2011) 396:1047–1053 DOI 10.1007/s00423-011-0833-4

ORIGINAL ARTICLE

Lean processes for optimizing OR capacity utilization: prospective analysis before and after implementation of value stream mapping (VSM)
Patrick Schwarz & Klaus Dieter Pannes & Michel Nathan & Hans Jorg Reimer & Axel Kleespies & Nicole Kuhn & Anne Rupp & Nikolaus Peter Zügel

Received: 19 November 2010 / Accepted: 26 July 2011 / Published online: 9 August 2011 # Springer-V erlag 2011

Abstract Background The decision to optimize the processes in the operating tract was based on two factors: competition among clinics and a desire to optimize the use of available resources. The aim of the project was to improve operating
In memoriam: Professor Dr. Jens Witte, 12 June 2003 P . Schwarz Department Block OP , Centre Hospitalier Emile Mayrisch (CHEM), Esch-sur-Alzette, Luxembourg K. D. Pannes Porsche Consulting, Bietigheim-Bissingen, Germany M. Nathan Centre Hospitalier Emile Mayrisch (CHEM), Esch-sur-Alzette, Luxembourg . Zügel H. J. Reimer : N. P Department of Surgery, Centre Hospitalier Emile Mayrisch (CHEM), Esch-sur-Alzette, Luxembourg N. Kuhn : A. Rupp Department Quality and Risk Management, Centre Hospitalier Emile Mayrisch (CHEM), Esch-sur-Alzette, Luxembourg . Zügel A. Kleespies : N. P Department of Surgery, Ludwig-Maximilian University (LMU), Munich-Grosshadern, Germany N. P . Zügel (*) General and Visceral Surgery Unit, Centre Hospitalier Emile Mayrisch (CHEM), Rue Emile Mayrisch, 4005 Esch-sur-Alzette, Luxembourg e-mail: nikolaus.zuegel@chem.lu

room (OR) capacity utilization by reduction of change and throughput time per patient. Setting The study was conducted at Centre Hospitalier Emil Mayrisch Clinic for specialized care (n =618 beds) Luxembourg (South). Method A prospective analysis was performed before and after the implementation of optimized processes. V alue stream analysis and design (value stream mapping, VSM) were used as tools. VSM depicts patient throughput and the corresponding information flows. Furthermore it is used to identify process waste (e.g. time, human resources, materials, etc.). For this purpose, change times per patient (extubation of patient 1 until intubation of patient 2) and throughput times (inward transfer until outward transfer) were measured. VSM, change and throughput times for 48 patient flows (VSM-A1, actual state = initial situation) served as the starting point. Interdisciplinary development of an optimized VSM (VSM-O) was evaluated. Prospective analysis of 42 patients (VSM-A2) without and 75 patients (VSM-O) with an optimized process in place were conducted. Results The prospective analysis resulted in a mean change time of (mean±SEM) VSM-A2 1,507±100 s versus VSMO 933±66 s (p <0.001). The mean throughput time VSMA2 (mean ± SEM) was 151 min (±8) versus VSM-O 120 min (±10) (p <0.05). This corresponds to a 23% decrease in waiting time per patient in total. Conclusion Efficient OR capacity utilization and the optimized use of human resources allowed an additional 1820 interventions to be carried out per year without any increase in human resources. In addition, perioperative patient monitoring was increased up to 100%. Keywords V alue stream mapping . Lean management . OR management

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Introduction Surgical procedures account for up to 50% of a clinic’s total budget. For this reason, solutions for optimal utilization of the available operating room (OR) capacity have to be identified in order to increase the number of operations. If the lean management tools value stream analysis and optimized value stream design (value stream mapping, VSM) are used, these expectations should be met. Through improved efficiencies of defined processes and elimination of waste change and patient throughput time are expected to be significantly reduced. By these means, increased capacities become available and can then be used to optimize patient monitoring, improving safety and quality, and additional operations. Furthermore, the reduction in throughput time contributes to patient satisfaction. The aim of these analyses was to develop a concept for a flexible and patient-orientated OR capacity utilization. The project was guided by an interdisciplinary team and supported by lean process experts (Porsche Consulting).

Method The VSM is a device which maps activities in a process and identifies the value-adding contribution to the final result (OR result) [1, 2]. Non-value-adding parts are considered as waste and will be eliminated whereas value-adding activities will be accounted of the processes in the future. The goal of VSM is to consolidate producing processes with the help of value-adding activities. Throughput timings determine the VSM and are characterized by four-time components: waiting, transporting, running and servicing time (flow). As a first step, the actual state of OR planning and OR control has to be described prior to defining a target state. The OR process is analysed and optimized. The key factors which have a substantial impact on OR process were (1) transparency and communication in OR planning, (2) making the first incision on time, (3) sequence stability and observation of capacity utilization for each discipline, (4) distribution and sequence of tasks as well as (5) logistics optimization. The aim of the study was the optimization of the OR schedule by utilizing the maximum and distribution of the OR capacities. We focused on the reduction of waste and augmentation of value-adding activities. Initial situation The Centre Hospitalier Emile Mayrisch (CHEM) with a capacity of 618 beds represents one of the specialist hospitals. Apart from the neuro and heart surgery, all other departments,

even including a national radiation therapy, can be found here. The centre offers a 24/7 service comprising nine OR theatres, 14 recovery rooms and 18 surgical intensive care beds as well as 180 beds in the surgery ward. In 2008, about 10,400 surgeries were performed in these nine OR theatres. The top 20 main surgeries (Luxemburgish pay scale [3]), lasting less than 1 h from incision to suture, make 80% of all operations. These pay scale numbers included the following surgeries ordered by decreasing frequency: 4G63 extraction of cataracts with artificial lens implantation, 2K63 resection of articulation, arthrodesis, arthroplasty of shoulder or knee, 2K46 arthrotomy of loose bodies, meniscal lesions or synovectomy of the knee, 2K33 osteotomy of realignment of bones, 6A61 Cesarian section, abdominally or vaginally, 2A21 cure of inguinal or femoral hernia or others, 6G86 curettage of uterus, dilation, 2F63 exstirpation of varicosis including crossectomy of the great saphenus vein, 2E90 total hip arthroplasty, 2L44 osteosynthesis without bone transplantation: humerus, elbow, both bones of the forearm, 2B21 cholecystectomy without other procedures of the bile ducts, 3L42 amygdalectomy, uni- or bilateral on a child <12 years, 2V94 lumbar arthrodesis (including transplantation), 5A41 surgery of phimosis (simple circumcision, without medical indication), 2E91 total knee arthroplasty, 6G82 hysterectomy, 2B22 laparascopy or intraoperative cholangiography of bile ducts or pancreas, 2L42 osteosynthesis without bone transplantation: one bone of forearm, wrist, patella, tarsal bones, 3R24 transtympanic drainage and 2V93 spinal disc herniation of the lumbar/thoracic region. Over 50% of these surgical procedures were performed by surgeons of orthopaedics/traumatology and visceral/ general as well as gynaecology/obstretics. In 2008, the central bed organisation planned the OR schedules without any OR specialist manager. All surgical procedures were documented over a period of several weeks and were illustrated in a process diagram (Fig. 1). V alue stream analysis (VSM, lean management) recorded all of the value-adding and non-value-adding activities in the process [4, 5]. The non-value-adding activities were considered as waste and divided into seven groups (1—overproduction, 2—inventory, 3—transport, 4— waiting time, 5—space, 6—journeys and 7—errors) [6]. Waiting times for patients are caused by multifactorial conditions and cumulated by subsequent processes. The main factor is that all ten stages of the process are triggered in Push system. Thus, a patient is transferred inward regardless whether there is capacity. Numerous stages are not synchronized with process requirements. Furthermore, reporting and documentation of data are performed by informational and conventional methods. The aim was to eliminate or minimize waste in order to create time for value-adding patient-oriented activities and Langenbecks Arch Surg (2011) 396:1047–1053 Nursing Anesthesia Surgeon Data server Change time 25‘ 7″ Cleaning Recovery room 1049 Patient handover Transport antechamber Antechamber Anesthesia Transport OR Preparation OP OP Dressing Recovery Transport air lock Outward transfer PRE-OP PERI-OP POST-OP Value added 1’11″ 4’3″ Waste Throughput time 2h 31′ 6’30″ 8’28″ 8’6″ 1’56″ 2’10″ 6’31″ 5’10″ 13’37″ 11’16″ 47’49″ 2’19″ 8’31″ 6’42″ 4’20″ 3’13″ 1h 35’24″ 3’1″ 6’7″ 55’36″ Fig. 1 V alue stream mapping initial situation 2008: Patient push = the previous transport; supermarket (defined inventory); pull = pull principle— process controls the subsequent process; the subsequent process controls the previous process; information flow electronic as a consequence this would lead to improved processes, optimal organization and reduced costs. Identification and time measurement of the weak points and waste (e.g. waiting for the patient, non-punctuality of operating surgeon, changes to the OR plan at short notice, interdisciplinary communication problems, change time instability and flawed logistics) were carried out using value stream analysis [Fig. 1; value stream mapping initial situation (VSM-A1)]. When evaluating the actual state in 2008, with respect to change times per patient (extubation of patient 1 until intubation of patient 2) and throughput times (inward transfer until outward transfer) using value stream analysis (VSM-A1), it became obvious that the available capacities have not been exhausted. This can be seen in the reduction of weak points and waste (Figs. 1 and 2). The major target criterion for optimizing VSM and avoiding waste was the reduction of waiting time for patients in the OR tract. The mean throughput time of the representing group of the year 2008 adds up to 2 h and 31 min and the waste of time to 55 min and 36 s. The main part was attributed to the waiting time (36%) (Fig. 1). With the help of the VSM analysis tool, process, staff and floor plan changes can be carried out and evaluated without having to intervene in the actual OR procedure. Clinical staff from all professional groups in the OR were involved on a regular basis in order to ensure the validity of the models (OR workshops). For further analysis, all operation times per patient in 2008 had been divided into four groups (surgery timing I, 0–1 h; II, 1–2 h; III, 2–3 h; IV , >3 h) (Table 1). This allowed to reflect on the distribution of time required for operations. Following the first value stream analysis (VSM-A1), the change times per patient and throughput times were determined as actual values for 48 representative patients in 2008 (Table 2). Since the operation time is determined by the surgeon and the available technologies (standards, materials), the distribution of operation time (value added) for each of the reference groups should be more or less in a similar range (Table 1). This first value stream analysis was evaluated as the initial situation (VSM-A1). Process optimization In order to improve the OR process, an optimized value stream (VSM-O) was in an interdisciplinary manner by VSM-A1. A core element is the switch from a Push system to a Pull system [i.e. the patients are only transferred inward when the OR gives the go ahead (Fig. 3)]. The change time was reduced using the single minute exchange of die (SMED) concept. This approach was developed by industry, just like value stream analysis, and is used to reduce the

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First incision
Anesthesia nurse
Prepara tion material Prepara tion anesthe sia Intubation Positioning Prepara tion material Extubation Prepara Outtion ward anesthe transfer sia Intubation

Second incision
Position

Prepara

Instrumentist tion OR
trays

Disin fection

Prepara tion OP table

Draping

OR organisation

Dressing OP site

Final positioning

Trays disposal

Disin fection

Prepara tion OP table

OR Draping organisation

Circulating nurse

Prepara Inward tion OR transfer trays

Positioning

Disin fection

OR organisation

Prepara tion OR trays

OR Reorganisation

Dressing OP site

Final positioning

OutPrepara ward tion OR transfer

Positioning

Disin fection

OR organisation

Anesthesia

Intubation

Extubation

Intubation

Surgeon

Positioning

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Draping

First incision

Suture first OP

Dressing Op site

Introduce Patient

Positioning

Second incision

OR cleaner

OR cleaning

Transfer nurse

Inward transfer

Patient 1

Patient 2

Fig. 2 Optimizing of the OR process clearly defined and parallelized in a timeline

set-up times of machines. For example, preparatory measures were moved from the OR to a holding area so that the patient could be anaesthetized and intubated immediately after entering the OR (external set-up) [7]. Detail optimization of the OR process was achieved primarily by visualization of the OR process modules. In contrast to direct transformation into a newly optimized value stream (Fig. 3), this presentation provides a better overview and facilitates understanding at all process levels (Fig. 2). The task distribution for each of the seven professional groups was clearly defined and paralleled in a timeline. Before arrival of patient 1, anaesthesia preparaTable 1 Distribution (number/percent) of operation duration =1 h; 1< n = 2 h; 2> n = 3 h; >3 h OP duration (h) n (total in 2008) % n (VSM-A1) % n (VSM-A2) % n (VSM-O) % =1 8,173 78.6 38 79.2 33 78.6 60 80 1< n = 2 1,641 15.8 7 14.6 7 16.7 12 16 2< n = 3 399 3.8 2 4.2 1 2.4 2 2.7 >3 187 1.8 1 2.1 1 2.4 1 1.3 Total 10,400 100 48 100 42 100 75 100

Total in 2008, VSM-A1 2008; VSM-A2 and VSM-O 2009 OP operative duration, VSM-A1 value stream mapping initial situation, VSM-O optimized VSM

tion as well as preparation of the OR and the OR trays has to be completed. Because of the long journeys and the limitations to plan journey times accordingly, a holding area with defined capacities was set-up. This is necessary in certain cases to avoid waiting times in the OR. At the same time, this holding area was used for anaesthetic procedures that were originally carried out in the OR. OR theatre 9, which was outside the central OR, had a maximum capacity of 30%. By reducing from nine to eight OR theatres, OR nursing staff was vacant (four full-time employees). They were integrated to the new holding area and further staff was not needed to be hired. The anaesthesia and OR nursing staff (each one person) from the holding area jointly take care of the completely pre-installed patient on the OR carriage for the final intubation. They connect the cables and prepare the anaesthetics. Simultaneously to transfer from the holding area to the OR theatre, the anesthesiologist is called and informed. In parallel, the instrumentalist prepares the sterile operating table with the help of the circulator nurse after having cleaned the hands. He or she also supports the anaesthesia nursing staff after the intubation by the anesthesiologist. The patient is positioned according to the instructions of the operating surgeon. Then, the patient is disinfected (circulating nurse/assistant) and the operating surgeons disinfected their hands. After surgical draping, the last step of OR preparation (OR nursing staff), the first incision can be done. At the same time, as the first incision

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Table 2 Mean change times±SEM (in seconds) and throughput times±SEM (in minutes) before (VSM-A1 +2) and after process optimization VSM-A1 (n =48) Change times (s) Throughput times (min) 1,309±81 155 min±11 VSM-A2 (n =42) 1,507*±100 151**±8 VSM-O (n =75) 933*±66 120**±10 Difference (VSM-A2 – VSM-O) 574 31 p value <0.001* 0.025**

VSM-A1 value stream mapping initial situation, VSM-O optimized VSM

and before summoning patient 2, preparation and control of the second set of OR trays had to be completed. Patient 2 was summoned before completion of the first operation (the operating surgeon determined the time for summoning) so that patient 2 could be transferred inward at the same time as patient 1 was being transferred outward. During evacuation of the OR, the trays and anaesthesia for patient 2 were prepared. The reversal of anaesthesia, dressing of the OP site, final post-operative positioning, disposal of trays and OR cleaning were all carried out simultaneously and smoothly. At the same time, patient 1 and patient 2 were transferred outward/inward. The steps that followed corresponded to the procedure for patient 1. The optimized value stream was recorded and time measurements were carried out (Fig. 3; VSM-O). At present, 1.3% of our patients are isolated—with increasing tendency. This means that every week 3 patients undergo the isolation process. Initially, the patient is transported

from the ward (isolated single room) to the operating theatre. All isolated patients are on the last position of the list of elective surgeries. They wake up from anaesthesia in ICA (isolated area) or ICU (single room) or later in ward. Thus, the core flow in the OR area will remain unaffected. Statistics The group time measurements were represented as mean values with standard error mean (±SEM). The independent analysis of spot checks was carried out using a t test (SPSS). P values less than 0.05 were considered significant.

Results After implementation of the new process, the two procedures were measured prospectively in 2009: 42 patients

Anesthesia

Surgeon Data server

Cleaning

Change time 15‘33″

Nursing

Handover Patient preparation

Transport OR

Anesthesia

Preparation OP

OP

Dressing Recovery

Transport Outward transfer

Recovery room

PRE-OP

PERI-OP

POST-OP

Value added 5’15″ 16’06″ Waste Throughput time 2h 5’5″ 0’26″ 7’14″ 3’7″ 6’42″ 4’13″ 52’8″ 4’33″ 4’38″ 2’5″ 7’41″ 0’47″

1h 28’43″

31’17″

Fig. 3 Interdisciplinary compiled optimized value stream mapping: Patient transport; supermarket (defined inventory); push = pull = pull the previous process controls the subsequent process;

principle—the subsequent process controls the previous process; electronic information flow

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from VSM-A2 versus 75 patients from VSM-O. Once again, the distribution of operation duration was similar for both groups (Table 1). After the interdisciplinary development of a VSM-O, the process was reduced from ten to seven and the Push system was replaced by the Pull one. Consequently, the following step was not initialized until the stage was prepared. Thus, waiting times could be reduced from 36% to 26% and value-adding activities increased about 10%. As a result, the total duration of the process was speeded up remarkably. The prospective analysis resulted in a change time mean value for the VSM-A2 group (mean+SEM) of 1,507 s±100 versus 933 s±66 for the VSM-O group (p <0.001). The mean change time could be reduced by a highly significant 38.1%. The mean throughput time for VSM-A2 (mean±SEM) was 151 min±8 versus 120 min±10 for the optimized changed procedure (p =0.025) (Table 2). This was equal to a significant decrease of 21% in the throughput time. The process optimization reduced the time of weak points and waste from 55 to 31 min (decrease of 44%). As a consequence, one additional operation per OR theatre and day might be considered, leading to an average occupancy of four beds per OR and day [8]. This would mean an increase of 1820 procedures per annum without any extra staff cost. For the year 2010, the prospective augmentation of the patient flow/p.a. was actually confirmed after optimizing processes and resulting allocations despite the closing of one OR theatre (from nine to eight). In 2009, an average of 1107.1 surgeries per OR theatre were performed. In the following year, there were 1266.9 operations per OR theatre. The difference achieved 156.6 more surgeries per OR theatre and finally 1256.8 surgeries/p.a. in addition (p =0.002; according to 70% of the forecast).

Discussion The sub-processes of patient change in an OR tract may appear to be unstructured to an outsider. On the other hand, the OR team and the OR specialist perceive them to be logical and ordered. Experience shows that it is possible to free up resources in established and optimized processes. It is recommended to ask for external expertise and support (e.g. as in this project Porsche Consulting) to identify this potential. The decision to increase the efficiency of the operating tract was based on two factors: competition among hospitals and cultural change (economy) within the professional groups. This enables cost orientation without a reduction in services or quality. In industry, especially in automobile industry, change timings mean a shutdown of the production. It is defined as the time period in which the last model leaves the

producing line and another model series start production. Projected to the operating sector, this stands for the time slot in which one patient is extubated and the following one is intubated. Meanwhile, the OR theatre is disinfected and preparations for the next patient are made. According to the philosophy of SMED, internal processes from the change timing were excluded in a form of a holding area. Furthermore, in this time slot, time tasks were performed in a parallel way (swinn lane planning). Emergency cases disturb elective procedures but were always transferred inward in the next vacant OR theatre. Eighty percent of the procedures at CHEM lasted up to 1 h. More than 47% of the change timings extended 30 min and more than 60% lasted more than 25 min. This proportion and duration are considered to be too high and too long in relation to the duration of the procedure. To effect an increase in staff motivation in the hospital and increase the efficiency of the OR teams, all relevant staff members were involved in the development of the process [9–11]. The procedures were simplified, making them more transparent. Process optimization in our clinic led to a change time reduction of 38% to 15.6 min with an OR capacity utilization exceeding 70%, placing it below the existing optimized times in other clinics (57 min Kiel, 16% [12]; 52 min Zurich, 20% [12]; 38 min Boston, 43% [8] and 27.7 min Gainesville, 37% [9]). Change times depended primarily on the operating surgeon, anaesthesia, nursing staff and logistics [13]. In the context of clinic internal, Critical Incidents Reporting Systems’s weak points in the patients’ monitoring were sorted out. With exception of few situations in the anaesthesia area, permanent 1:1 assistance for the patient was always guaranteed.The elimination of unnecessary and stressful waiting times prior to the next operation and the acceleration of the throughput time freed up human resources who can, if used properly, optimize the quality of care and patient safety. Using the Pull system and the SMED, our existing team could provide 100% continuous patient care [8, 12]. Given that an OR minute costs €7, the reduction of total change time by 28.8 min per OR results in a time saving corresponding to approximately €366 k per year for seven ORs as well as an increase in revenue of 20–30% (budget increase €1,130,000) [7, 10]. In addition, a standardization of treatment methods (standard operation procedures) led to an improvement in the productive time of operating surgeons and OR capacity utilization [14]. The processes resulted in transparency and simplicity. The team-orientated specialized OR processes increased the quality and operational organisation and led to an improvement in patient safety (risk management). Our experience showed that additional staff is not necessarily required. In the former process, the patient was often ordered too early. As the previous patient was still in the OR theatre, the successive patient could not be monitored in an optimal way.

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This security risk was eliminated with the introduction of the holding area and the process optimization (Pull system). Additionally, the patient’s security could be enhanced by the implementation of the WHO checklist. Due to the increase of value-adding activities (focusing of nursing competences) the staff ’s motivation improved (staff ’s survey); last but not least, also because of the multidisciplinary development of the processing [9–11]. Today, sensitive data such as throughput, cycle and change time and point of time of the first incision are continually monitored. In the OR theatre, the data are presented in public via a dashboard. By doing so, feedback and detection of the process efficiency and stability are guaranteed.

References
1. Georges ML (2003) Lean Six Sigma for services. Mcgraw-Hill; ISBN: 0-07-141821-0 2. Trusko E, Pexton C, Harrington HJ, Gupta P (2007) Improving healthcare, quality and cost with Six Sigma. Financial Times Prentice Hall; ISBN: 0-13-174171-3 3. Nomenclatures des actes et services des medecins et medecinsdentistes. 2008–10:1–68 4. Rath F (2008) Tools for developing a quality management program: proactive tools (process mapping, value stream mapping, fault tree analysis, and failure mode and effects analysis). Int J Radiat Oncol Biol Phys 71(1 Suppl):S187–190 5. Wojtys EM, Schley L, Overgaard KA, Agbabian J (2009) Applying lean techniques to improve the patient scheduling process. J Healthc Qual 31(3):10–15, quiz 15–16 6. Liker JK (2003) The Toyota way. The Mc Graw-Hill Organs; ISBN 007–1392319 7. Hanss R, Buttgereit B, Tonner PH, Bein B, Schleppers A, Steinfath M, Scholz J, Bauer M (2005) Overlapping induction of anesthesia: an analysis of benefits and costs. Anesthesiology 103 (2):391–400 8. Sandberg WS, Daily B, Egan M, Stahl JE, Goldman JM, Wiklund RA, Rattner D (2005) Deliberate perioperative systems design improves operating room throughput. Anesthesiology 103 (2):406–418 9. Cendán JC, Good M (2006) Interdisciplinary work flow assessment and redesign decreases operating room turnover time and allows for additional caseload. Arch Surg 141(1):65–69, discussion 70 10. Matern U (2009) Der Experimental OP . Betriebswirtschaft, Patientensicherheit und humanitäre Patientenversorgung sind keine Gegensätze. Der Chirurg BDC 3:149–153 11. Stepaniak PS, Mannaerts GH, de Quelerij M, de Vries G (2009) The effect of the operating room coordinator ’s risk appreciation on operating room efficiency. Anesth Analg 108(4):1249–1256 12. Sokolovic E, Biro P , Wyss P , Werthemann C, Haller U, Spahn D, Szucs T (2002) Impact of the reduction of anaesthesia turnover time on operating room efficiency. Eur J Anaesthesiol 19(8):560–563 13. Bauer M et al (2007) Intraoperative Prozesszeiten im prospektiven multizentrischen V ergleich. Dtsch Aerzteblatt 47:A3252–3258 14. Martin J, Schleppers A, Kastrup M, Kobylinski C, König U, Kox WJ (2003) Entwicklung von Standard Operating Procedures (SOPs) in der Anästhesie und in der Intensivmedizin. Anästh Intensivmed 44:871–876 15. Stahl JE, Sandberg WS, Daily B, Wiklund R, Egan MT, Goldman JM, Isaacson KB, Gazelle S, Rattner DW (2006) Reorganizing patient care and workflow in the operating room: a cost-effectiveness study. Surgery 139(6):717–728 16. Mende H (2009) Prozesszeiten in der Anästhesie—Werkzeuge für ein effizientes OP-Management. Anästhesiol Intensivmed Notfallmed Schmerzther 44(7):544–547

Conclusion The OR throughput time was reduced by 22.4%. Given an average of four operations per OR/day, an additional operation per OR could be scheduled in the future [15]. This has been an increase of 1,257 surgical procedures annually, without additional staff. The change time was reduced by 38%. In addition to reducing throughput time, 9.6 min could be saved per change, resulting in an additional capacity of 28.8 min per OR. The introduction of the Pull system guaranteed a 100% patient monitoring. Furthermore, nursing activities could be introduced to the process at an earlier stage and carried out more efficiently. Making the first incision on time, sequence stability, reduction of change times and transfer times increase the utilization of available OR capacity. This requires close synchronization between staff and physician which has a substantial impact on the treatment and patient’s satisfaction in the OR tract [16]. Furthermore, this process improvement helps to secure the business location and in doing so, contributes to the retention of human resources.
Acknowledgment The valuable assistance of Ms. Lisa Gambhir, MD is highly appreciated. Conflicts of interest None.