The Development And Empirical Research Of An Intervention Program Based On Human-Machine-Environment Science System Theory To Reduce The Level Of Lumbar And Back Muscle Fatigue Related To Nursing Operations In ICU Nurses

Accumulation of muscle fatigue is an important pathogenic mechanism of occupational low back pain in intensive care unit(ICU)nurses,and working in unneutral posture is an important cause related to muscle fatigue in lower and back region among this staff.Objectives:The aim of this study included 4 aspects as followed:(1)Based on the researching framework of Muscle Fatigue related to Nursing operation(MFr NO)in lower and back region of ICU nurses which was integrated from human-machine-environment science system theory and process optimization principles,we aimed to explore the current situation of low back MFr NO in this population and the experience of low back muscle fatigue degree in the process of different nursing operations from quantitative perspectives,and to find out the breakthrough point to solve this clinical problem from the dimensions of human,machine and environment.(2)To specify the specific procedure steps,the nursing operations and the high-risk post that leading to low back MFr NO in ICU nursing,and to quantify the degree of postural hazard and subjective fatigue intensity in the process of ICU nursing operating.(3)To construct an intervention program to reduce low back MFr NO for ICU nurses.(4)To implement the intervention plan,and then to evaluate its rationality,effectiveness and extensibility.Methods:This project included 4 phases:(1)This was a group interview of ICU nurses focusing on low back MFr NO.Eight ICU nursing managers and ten ICU bed-beside nurses were recruited from a tertiary general hospital to conduct group focus interviews.The data were stored and analyzed by using content analysis method with NVivo11.0.Thematic analysis was used for data analysis.(2)This was a field observation on characteristics of nursing working conditions in ICU.Two ICUs of a tertiary general hospital were selected as fields,named field A and field B.We were introduced to field A and field B for field observation by the head nurse of the department from November to December in 2021.A total of 45 nurses(22 in field A and 23 in field B)were observed when they were on daily bed-side nurses duty by focus observation.Data collection includes three parts:(1)the working posture’ collection and analysis.Smart phone was used to record the video data of nursing procedure including morning nursing,turning and knocking patients’ back and transferring patients from the bed to transportation tools,ovako working posture analyzing system(OWAS)was used to analyze these posture data,and the hazard degree of working posture of ICU nurses was evaluated according to Action Categories(AC).AC1 means it’s normal posture,no handling required;AC2 equal to slight hazard in posture,and immediate improvement measures should be taken;AC3 means the posture has obvious harm,and improvement measures should be taken as soon as possible;and AC4 means it is seriously harmful and immediate improvement measures should be taken.(2)We chose subjective fatigue rating scale to assess subjective fatigue strength in the process of nursing operating dynamically.(3)Nurses’ behavior Scale for prevention of occupational low back pain was used to assess the ability of nurses to prevent occupational low back pain based on the questionnaire Star platform.The chi-square test and general multivariate linear model were used to explore curve rules pf working posture hazards score and subjective fatigue in the process of nursing operating.(3)This phase was to develop an intervention plan based on the researching framework of Muscle Fatigue related to Nursing operation(MFr NO)in lower and back region of ICU nurses.An intervention plan construction team was established.The first draft of the plan to deal with MFr NO in the low back of ICU nurses was constructed from the three elements of human,machine and environment after group discussion.Finally,after expert consultation and pre-experiment,the intervention program aimed to reduce MFr NO in the region of low back in ICU nurses was constructed: Love your Low Back.(4)Implementation and verification of "Love your Low Back" program.This was a self-controlled before and after experiment design.We recruited 40 ICU nurses and one standardized patient.Before intervention,the subject simulated two nursing programs-turning and knocking patients’ back(double cooperation)and manual transferring a patient from the bed to transportation tool(double cooperation).Three-dimensional camera motion capture was used to obtain the whole process and omnibearing operation image data,and OWAS was used to analyze the hazard degree of working posture(AC degree).RPE was selected to timely report the degree of subjective fatigue at low back region,and subjects were given smart bracelets to dynamically collect the indicators of heart rate(HR)and blood pressure(BP).After the intervention named Love your Low Back,all subject simulated the two nursing operation again and all data were collected as above.Paired sample t-test was used to evaluate the effectiveness of the intervention program,and semi-structured interview and five-point questionnaire were used to evaluate the rationality and extensibility of the program.Results:(1)In the qualitative research results,the group interview results proposed the following six themes: the problem of low back fatigue and pain are common in ICU nurses,they work in unneutral posture most of their working time,healthy working culture was poor in hospital,the human mechanics principles of young nurses are not well applied in practice,the lack of healthy nursing operation procedure,and the auxiliary equipment of weight-bearing operation is insufficient,and the function can not meet the clinical needs.(2)During the field observation period,the Barther index of 304 patients in ICU was ≤40.(1)Analysis of nurses’ nursing working posture:78981 valid pictures were obtained in the two fields,of which52779 were bad working posture with hazard,accounting for 66.9%,17560(22.2%)were AC4 in urgent need of improvement,and 12701(16.1%)were AC3 in need of improvement as soon as possible.Among the three nursing operations of morning care,turning and knocking patients’ back and manual transferring a patient from the bed to transportation tool,the proportion of AC4 plus AC3(50.3%)accounted for the highest,followed by manual transferring operation(33.6%).There was a significant difference among three groups(=1839.443,P<0.001).The results of the three postural hazard scores showed that the average score of point 4(carrying)in the procedure of transferring patients was the highest(3.0±0.3),followed by point 4(back tapping,2.9±0.4)of the procedure of turning and knocking patients.There were differences in the postural hazard scores of each time point in the three tasks(all P <0.001).(2)Lumbar and back subjective fatigue score: the average score in the time point 4(back tapping)of the procedure of turning and knocking patients was the highest(6.8±1.7),followed by the time point 4(handling,4.7±1.1)in the procedure of transferring patients.There was a difference in RPE at each time point in the three tasks(all P <0.001).(3)The score of nurses’ Prevention of occupational low back pain behavior Scale: the total score of the scale was 117.5±17.8(P25=107,P75=129),and the score rate was 81.0%(P25=73.8%,P75=89.0%).The score rate of attitude dimension was the highest(87.9%,22.0±2.96),and the score of facilitation dimension was the lowest(26.6±5.22),with the score rate of 76.0%.(3)In the construction phase of the intervention plan,a total of 8experts from occupational health,critical care management,human factors engineering,clinical medicine and spinal surgery and 5 ICU nurses participated in the construction of the plan.Based on the research framework of low back MFr NO of ICU nurses formed in the early stage,the intervention program of low back MFr NO of ICU nurses was constructed with "reducing unneutral working posture" as the core.After expert consultation,group discussion feedback and pre-experiment,the MFr NO intervention program for ICU nurses was formed.The intervention program module was set up centering on improving the prevention knowledge,attitude and skills of MFr NO prevention for ICU nurses,adding simple equipment,optimizing the operation process(two procedure: the procedure of turning and knocking patients and the procedure of transferring patients),and promoting the construction of healthy working culture.The 6-week intervention period was named "Love your Low Back",in which we designed offline and online modules crossly and the combination of medical theory and clinical practice.(4)Implementation effect of the intervention program: 40 subjects(100%)successfully completed the intervention study.1)Changes in working posture: we obtained 10856 effective pictures in baseline measurements and 12001 for measurements after the intervention for turning and knocking simulating operation.The proportion of unneutral working posture decreased from 72.7% to 59.5%after the intervention,and there was a significant difference in the distribution of the level of posture hazards(=3205.662,P<0.001),and the proportion of AC4 decreased by 28.8% from 29.6% to 0.8% after intervention.Postural hazard score showed a significant downward trend,from 2.5±0.3 to 1.7±0.1(t=17.211,P<0.001).We obtained 6453 effective pictures(single position)in baseline measurements and 5532 for measurements after the intervention for manual transferring simulating operation.The proportion of unneutral working posture decreased from65.7% to 50.9% after the intervention,and there was a significant difference in the distribution of the level of posture hazards(=618.447 a,P<0.001).The proportion of AC4 decreased from 15.9% to 4.8%,with a difference of 11.1%.Postural hazard score decreased from 2.2±0.2 before intervention to 1.7±0.2(t=13.247,P<0.001).2)Improvement of low back subjective fatigue: the RPE score of the five time points in the process of turning and knocking simulating operation decreased with a range of 0.35 to 1.94(P <0.05).The RPE value of the time point 4(percussion back)decreased from 6.9±1.7 before the intervention to 5.9±1.4,with a difference of 1.4±0.9(t=2.446,P=0.019).In the process of manual transferring simulating operation,The results of RPE at five time points after the intervention showed a downward trend compared with those before the intervention,ranging from 0.73 to 1.86,with the most significant decline at time point 3(all P values ≤0.001)3)The comparison of the subjects’ heart rate before and after the intervention showed that the subjects’ heart rate decreased after the intervention compared with that before the intervention,and the decrease range was between 1 and 9 times/min,especially at time point 4(knock back)(t=-3.794,P=0.001).4)In the overall evaluation,the item "This program is worth promoting" got the highest score(4.63±0.49),the item "reasonable arrangement" and "reasonable and feasible optimization process" got higher score of 4.58±0.50,and the item "can stimulate me to improve the awareness of healthy operation" got one high score of 4.43±0.50.Conclusions:(1)The problem of MFr NO in low back among nurses is common.The knowledge and skills of MFr NO prevention in the low back of nurses need to be improved.There is a lack of auxiliary equipment for weight-bearing operations such as turning over and carrying,and the low back protection of preventive operators is not fully considered in the ICU nursing operation process.The healthy working culture needs to be improved.(2)During the process of nursing procedure implementation,the incidence of unneutral working posture of ICU nurses is high,)the degree of harm of working posture is high,and the subjective fatigue of the lower back is serious.The time point 4 in the process of turning and knocking simulating operation(tapping back)and the time point 4 of in the process of transferring patients need to be optimized urgently.(3)The research framework of low back MFr NO in ICU nurses based on the theory of man-machine-environment can be used to guide the development of health operation intervention programs in ICU.From the perspective of the three elements of man,machine and environment as the breakpoint,this framework focused on how to improve the operators prevention knowledge and skills,introducing simple equipment,optimizing operation process,and the elimination of high degree unneutral working posture along with strong fatigue,and how to create a healthy cultural atmosphere.(4)The "Love your Low Back" program that fully follows the human-machine-environment theory can help ICU nurses improve their awareness of healthy work,reduce the occurrence of unneutral working posture,reduce the harm degree of working posture,and reduce the subjective fatigue degree of the low back.The intervention program is reasonable and feasible,which can be further extended to the development of other occupational musculoskeletal injury prevention programs.