Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT04477746 |
| Other study ID # |
FHMREC19052 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
November 12, 2020 |
| Est. completion date |
March 30, 2022 |
Study information
| Verified date |
September 2022 |
| Source |
Lancaster University |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational
|
Clinical Trial Summary
Musculoskeletal injuries amongst surgeons are prevalent. This project will determine whether
Robotic-assisted Laparoscopic surgery (RALS) offers superior benefits to surgeon's
musculoskeletal health than standard laparoscopic surgery (LS), by identifying the
comparative changes in muscle fatigue during RALS Vs LS surgical procedures, and additionally
identify any cognitive effects of this. The Study if successful, could help reduce injury
rates in surgeons.
Description:
The number of surgical procedures being performed using minimal access techniques is on the
rise because of improved recovery times for patients. Thus, surgeons are performing an
increasing number of endoscopic/laparoscopic procedures and are operating for longer periods.
A recent meta-analysis showed that work-related musculoskeletal injuries amongst surgeons are
common (1) and surgeons are amongst those most at risk of work-related musculoskeletal
decline (2). Indeed, the prevalence of degenerative spinal disease is 17%, rotator cuff
pathology 18%, and degenerative lumbar spine disease is 19% (1). Surgeon's experience
work-related musculoskeletal pain in addition to injury, and pain is highly prevalent in the
neck (48%), shoulder (43%), and back (50%) (13).
According to the Office for National Statistics in the UK, musculoskeletal problems amongst
the workforce are the second most common cause for absence (17.7%) and account for 23 days
absence/year (2). This is not dissimilar in the US where the Bureau of Labour Statistics
estimates that 62% of all worker injuries and 32% of missed days from work result from
musculoskeletal problems. Collectively, these data suggest that musculoskeletal problems
caused by careers in surgery can reduce physical health, which is associated with reduced
productivity, career longevity, and even the quality of patient care.
Robotic-assisted laparoscopic surgery (RALS) is a modern technology that could help mitigate
these musculoskeletal problems and thereby improve patient care. In comparison to standard
laparoscopic surgery (LS), RALS offers steadier wrist movements with a reduced fulcrum
effect, thus benefiting the patient (3). There is emerging evidence that RALS is associated
with a lower rate of musculoskeletal problems (23-80%) than LS (70- 100%) (1). RALS may
therefore be an attractive alternative to LS, despite the high cost of equipment and steep
learning curve during training.
No study has compared the demands of RALS vs. LS on musculoskeletal fatigue (and subsequent
injury risk) and whether these changes are underpinned by changes in cognitive fatigue. The
investigators aim to determine whether a career using RALS is associated with better
musculoskeletal health for surgeons than standard LS when performing complex minimally
invasive procedures.
The hypothesis is that RALS will reduce musculoskeletal fatigue and the prevalence of
musculoskeletal injury in surgeons compared to LS. If this is true, RALS should receive
increased support through preserving surgeon's health and thereby reducing costs for
healthcare providers.
Research subjects (surgeons and patients) Surgeons: Investigators will recruit surgeons
completing surgical procedures who have similar levels of experience between RALS and LS
groups. Surgeons will fill a questionnaire regarding working hours and experience, physical
activity level (e.g., sport, bicycling to work or gardening), general health conditions and
musculoskeletal symptoms within the last 12 months using the Standardized Nordic
questionnaires for the analysis of musculoskeletal symptoms (11). The investigators will also
quantify body composition (height, body weight, BMI, muscle mass, fat mass) using
clinically-validated bioelectrical impedance analysis. Surgeons will broadly be matched for
age and surgical experience, anthropometry, and sex. Patients: To complete the work, the
investigators will use data from n = 40 patients being operated upon in RALS and n = 40 LS
groups that will be age, sex, BMI, and pre-operative risk score matched.
Surgical procedure and overall study design Data will be collected during index procedures:
For example prostatectomy or anterior resection using either RALS or LS. Before surgery,
surgeons are fitted with both EMG (to measure muscle fatigue) and EEG (to measure cognitive
fatigue). Surgeons will complete a series of validated questionnaires before and after each
surgery to subjectively determine musculoskeletal strain/pain and cognitive fatigue.
This research is being conducted in real-life surgery and controlling conditions between
operations is uniquely challenging. The study will exclude any operations where complications
result in the surgery taking beyond 50% of the mean average surgery time, to prevent this
skewing the data towards an effect for musculoskeletal fatigue. This mean average time will
also include for specific procedures e.g. Prostatectomy - defining resection margins by
dissecting the endopelvic fascia and mobilising seminal vesicles, rectum and bladder neck,
defining and transecting the prostatic pedicles; transecting the bladder neck, urethra, and
prostate; anastomosing the urethra to bladder neck. Bowel surgery - identifying, transecting
and ligating the pedicle; lateral mobilisation and preserving ureters, and bowel anastomosis.
The investigators will assess acute fatigue by comparing RALS and LS within a single surgery
that is the first surgery of any given day. To determine the cumulative fatigue (chronic
effects of surgery, aim 2), comparison will be made between the subject's first and last
surgery of the day when >2 surgeries have been completed.
Measurement of musculoskeletal fatigue (EMG) EMG justification. The study will utilise
electromyography (EMG) to determine acute and chronic changes in musculoskeletal demands
associated with RALS and LS surgery. Surface EMG is a non-invasive procedure that measures
muscle activity by recording the electrical signal generated during muscle fibre recruitment.
Its ability to assess fatigue has been long established (e.g. (4)) and it has been widely
used in many populations, including athletes (e.g. (5)), dentists (6) and surgeons (e.g.
(7,8)) EMG will be collected for 200 s (9) at 0, 30, 60, 90 and 120 minutes of a ~2-hour
surgical procedure. In addition to these time points, EMG data will be collected during
clinically important tasks (e.g. suturing upon completion of surgery, which typically will
take 10 minutes).
EMG protocol. Surgeons will provide written informed consent prior to participation. Surgeons
will be completing index procedures: For example prostatectomy or anterior resection using
either RALS or LS; the protocol for EMG data collection will be identical. Before surgery,
surgeons will be fitted with wireless EMG sensors. The EMG data collection procedures will
follow established protocols regarding site preparation and electrode placement, as well as
data collection, processing and normalisation (7,12). Briefly, the site will be shaved and
cleansed with alcohol wipes, with the bipolar electrodes placed on the belly of the muscle
and parallel to the muscle's fibres having an inter-electrode distance of 20mm (12).
Electrodes will be placed on muscles of the arm, neck, shoulder and back e.g. flexor carpi
radialis muscles, biceps muscle, bilaterally from the trapezius muscles, and bilaterally from
the erector spinae muscle. These muscles have been selected based on a recent meta-analysis
(13). Electrodes are fitted before surgeons' scrub for surgery and electrodes will be covered
by surgical gowns thereby maintaining a sterile theatre. A wireless EMG system has been
selected so that it is minimally invasive and does not impede a surgeon's movement with
wires.
EMG data analysis. Data will be collected and analysed using EMG Works (Delsys Inc., Boston,
MA, USA), with recommended normalisation, sampling, filtering and smoothing techniques (7).
EMG recordings in previous data show significant changes during LS procedures in 70 - 85% of
surgeons, mainly in neck, shoulders, hands, lower back, and lower extremities muscles. The
recordings from muscles of the arm, neck, shoulder and back will be monitored but lower limb
muscles will not be included because during RALS, Surgeons are seated away from the patient
and having brow- and armrests considerably modifies the workload on the lower limbs making
comparisons of lower-limb muscles in LS not meaningful. Once the EMG signal has been
normalised (10), basic EMG variables, such as frequency and amplitude, can provide
information on how muscle fibre recruitment has changed, both at a single muscle as well
across several muscles (activation / recruitment strategies), while a fatigue score can also
be calculated (11). The normalisation process can afford the ability to compare between
muscles as well as examine the muscles' activity different time points (i.e. within the same
session or after a longer time has elapsed; e.g. (5,12,13).
Measurement of cognitive fatigue (EEG) EEG justification. The study will use
electroencephalography (EEG) to determine if acute or chronic changes in musculoskeletal
demands are associated with changes in motor control and cognitive fatigue. Cognitive fatigue
can be determined via neurophysiological measures, such as the electroencephalogram. The EEG
can measure the ongoing electrical activity of the brain during a given task, such as whilst
driving or during surgery. EEG measures of fatigue can provide an objective quantification of
an individual's cognitive state in real-time, removing reliance on subjective measures such
as self-report or questionnaires that have been found to be unreliable for moderate fatigue
states. The brain oscillates at a number of different frequencies at any given time, and this
information is recorded in the EEG. The power of certain frequency bands has been taken as a
proxy to index cognitive fatigue. Specifically, evidence indicates that alpha-band power
(7-13 Hz) is sensitive to fatigue (for a review see (14)), and has been used to measure
driver fatigue both in real-traffic and simulation exercises (15- 18). When fatigue
increases, alpha-band activity occurs in bursts of 500 milliseconds, which are known as alpha
spindles (19). Alpha spindles are considered to reflect individual fatigue states and can be
quantified in terms of their peak frequency, duration, and amplitude, giving rise to an
individual's alpha signature (20).
EEG protocol. Whilst surgeons are having EMG electrodes fitted, a similar procedure will be
completed for the wireless EEG electrodes. The skin site on the head will be prepared as
previously described (21) and the electrode gel and electrode cap will be applied before the
surgical cap, thereby maintaining the sterility of the surgical theatre. Electrodes will be
placed over the cortex using an 8-channel electrode montage to record ongoing EEG
oscillations during surgery for 200 s (9) at 0, 30, 60, 90 and 120 minutes of a ~2-hour
surgical procedure. Electrodes will be positioned according to the 10-20 international
electrode placement system. The main EEG channels of interest will be positioned over the
occipital and parietal cortex, namely electrode locations O1, O2, P3, P4, P7, P8 where
maximal alpha activity can be detected. In addition to these time points, EEG data will be
collected during clinically important tasks (e.g. suturing upon completion of surgery, which
typically will take 10 minutes). A wireless EEG system has been selected so that it is
minimally invasive and does not cause distraction or restriction due to movement of wires.
EEG data analysis. Data will be collected and analysed using Enobio 8 5G (Neuroelectrics,
Cambridge, MA, USA) using standard referencing, sampling, filtering and smoothing techniques
(21). Investigators will compare peak alpha power, and alpha spindle duration and amplitude,
in RALS compared to LS. Changes in EEG power spectra, specifically in the alpha frequency
band, will be used to monitor alertness, and will provide crucial information about whether
cognitive fatigue, underpins any musculoskeletal fatigue. The study will also be able to
identify how alertness changes over time during surgery through the EEG power spectra.
Measurements of surgeon physical activity and musculoskeletal health It is vital that
musculoskeletal fatigue in the surgeons is not influenced by anything other than the work
environment. We will use tri-axial accelerometery every week throughout data collection to
measure and ensure surgeons are not changing their physical activity patterns (and thus
getting stronger or weaker). Nutrition is also critical in the development of strength, just
like poor nutrition can lead to strength loss. Therefore, surgeons will complete 3-day food
diaries and dietary analysis at weekly intervals throughout the data collection period.
Statistics and data analysis. Power calculation: To address aim 1, The investigators
anticipate a difference in musculoskeletal fatigue of 20% between RALS and LS based upon the
limited evidence available (1). Therefore, based on a predicted effect size (Cohen's d) of
0.82, recruitment of 40 subjects in RALS and 40 subjects in LS (total sample size n = 80)
will be carried out. These numbers will be matched between prostate and bowel surgeries. In
aim 2, data suggest that the level of fatigue between the last surgery of the day versus the
first will be greater than the difference in aim 1 (Cohen's d 0.90), therefore 27
subjects/group are required for this research question. Lastly in aim 3 to investigate
whether changes in musculoskeletal fatigue are underpinned by changes in motor control and
cognitive fatigue, The investigators anticipate an effect size of 0.85 between RALS and LS
and therefore will use data from the 31/group to study this effect. An A priori power
calculation will be used to compute the required sample size using G*Power 3 (22).
Conservatively, the lower of the three values for the power calculation (an effect size of
0.82) has been chosen. Assuming a Cohen's d of 0.82 requires 40 participants per group for
90% power to detect a difference between groups, at an alpha of 0.05.
Statistical analysis: To determine differences in musculoskeletal and cognitive fatigue in
RALS and LS, a mixed-model ANOVA or non-parametric equivalent will be utilised. The data and
conclusions arrived at the end of the study will inform recommendations both in scientific
literature (publications) and dissemination at conferences towards the end of the project
(see Gantt chart). The study is the platform to develop a strong case regarding the long-term
musculoskeletal effects on surgeons performing minimal access procedures in RALS.
