6/8/2020 Animal Surgery Simulator Videos
Surgeon Simulator 2013 is a darkly humorous over-the-top operation sim game where you become Nigel Burke and perform life-saving surgical maneuvers on passive patients.
It's Life Jim, But not as we know it:Complete the first surgery, the heart surgery. Just remove the ribcage with hammer, saw, circular saw or drill, take out the lungs. Then cut the arteries with a scalpal and replace with the heart in the box.Kali Mah!:Complete the heart surgery in under 2 minutes. This was a tricky one.
I would use the drill to remove the centre of the ribcage and only the right side ribs, pull out the right lung and cut from there. Takes a few tries.Socialised Medicine:Perform the heart surgery losing less than 1500ml of blood (to 4100ml). Not too hard, use the drill or circular saw to remove the ribcage, be careful not to make him lose blood.
If he does, stab him with the green needle.Nine Nine Nine!:Perform a heart surgery in a ambulance. This was hard at first. Try and follow the same steps as Kali Mah!, and be careful of when the ambulance moves around.Life's Too Short:Perform the ambulance heart surgery in under 2 minutes 30 seconds. Same as above, really, takes some practice, try Kali Mah!
A few times beforehand to get practice at this.One With The Speed Bumps:This was my penultimate achievement, very hard. Complete the ambulance heart surgery losing less than 2000ml of blood (to 3600ml). For this I reccomend throwing a lot of stuff away so it dosnt bash into the guy and make him lose blood. Throw in this order: Fire Hydrant (far right), Hammer (desk on left), Oxygen Tank (Left in cupboard) Axe (desk on right) Radio (If this hits his head, he loses blood) (desk on left), Circular saw (desk far left).
Then use the drill to remove his ribs. When you're done with it, throw it. Be careful of scalpals flying into him too.I Think I've Got This:Perform the brain surgery (3rd). Use any tool to bash open his skull, grab his brain out, then scalpal/axe the centre of the brain tube so it falls out. Grab the new brain in the water and put it in. Easiest operation IMO.How Long Can You Live Without A Brain?:Perform brain surgery in a minute.
Not too hard, just remember to break all around the skull to pull it out. Use hammer.Sweet Blasphemy:Perform brain surgery losing less than 600ml of blood (to 5000ml). Quite tricky too, use circular saw and go around the edge, dont to hit the brain, or he will lose lots of blood. Be careful with axe/scalpal, try and make the tube exposed. If its not working, try the laser, believe me, it helps a lot.What Could Possibly Go Wrong?:Perform the brain surgery in an ambulance.
Not too hard, similar to normal. His head has a bigger chance of flopping to one side.Brainstorm:Perform ambulance brain surgery in under 1 minute 15 seconds. Again, similar to normal.Nigel You Bloody Hero:Perform ambulance brain surgery losing less than 1200ml of blood (to 4400ml). Quite hard, similar to normal again, but takes quite a bit of practice.
Use fire hydrant to break skull. (It works!)You've Got To Be Kid'n'ey!:Perform the double kidney operation. Hardest at first, but its easy once you get it. Dont cut the ribs whatsoever, he just looses loads of blood. I reccomend using the knife that has a kidney shaped handle on the left desk, but if you throw it away a normal scalpal will suffice.
The places to cut are slightly red and have lines on them. For reference, the large intestine comes loose when you cut the part at the lower right and the middle left (Where it connects at the small intestine.) The small intestine is cut at the lower left and where it connects to the stomach. Also cut the stomach off where it connects to the oesophagus. Pull everything out, and you see a liver. THIS IS VERY HARD TO PULL OUT. You need to poke it and grab it a bit, so it starts making squish noises and flops around. It should come loose with a bit of that.
Then cut the kidneys off at the yellow pipe and replace them.:DDon't In-Test My Patience:Perform kindey surgery in under 2 minutes 50 seconds. Kinda hard with that liver in the way, but you can remove it if you have time, or try and flip the kindey out with the knife. Definately use the kindey handle knife for this, dont throw it.Performance Anxiety:Perform the kidney surgery losing less than 500ml of blood (to 5100ml).
Not too hard, just dont cut the ribs at all, and be careful with the knife. Use the kidney handle knife again. Angle the knife so you can see where you are cutting.When You Have No Choice But To Operate:Perform kidney surgery in an ambulance. Seems hard at first, but actually a bit easier, as the kindeys fly out when you cut them, so the liver dosnt get in the way.A Surgeon's Merit Is Based On Speed:Perform ambulance kidney surgery in under 3 minutes. Not too hard, requires some practice though.At Least He Won't Be Peeing Blood:Perform ambulance kidney surgery losing less than 600ml of blood (to 5000ml).
Kinda hard too, just try and use that kindey handle knife. Again, comes with practice.Shh I Doctor Now:Calm Bob despite him being under anesthetics. Press A, W, E and Space, so you only have your index (4th from left) showing, then put it over the patients mask and wiggle around a bit.Flippin' The Bird:Show how much you hate Bob for having all these problems by giving him the middle finger. Press A, W, R and Space so the middle finger remains (3rd from left), then turn the hand so you're not swearing at yourself, but at Bob. Wiggle around a bit.Surgery Horns:Nigels ears are messed up and that surgery music you hear is death metal in his ears, show your appreciation of metal with a finger gesture. Press W, E and Space so only the little (1st from left) and index 4th from left are showing. Then hold right click and move your hand up and down.Pinky Swear:Tell the ribs they arent about to be smashed with a hammer by pinky swearing.
Press, W, E, R and Space so only the little (1st from left) finger remains. Then touch the ribcage.Surgetricity:Perform a surgery whilst electrocuted. To electrocute yourself, grab somthing metal, like a scalpal or somthing, then jab it into the sockets. This will reverse your controls. Do this within 10 seconds and do a surgery. I reccomend the brain, since its easiest.
This will be quite confusing, and youll find yourself reverse controlling even after you do it!Performance Enhancer?:Perform a surgery whilst drugged. To drug yourself, inject yourself with the green needle/syringe. This will make you hallucinate. Youll see a green and purple version of the screen, and sounds sound slowed. Do this in 10 seconds, then do a surgery.
I reccomend brain surgery again. Not as hard as electrocution, but as advice I would look at the green version of yourself only. If you want to reverse this, inject yourself with the blue needle.I Immediately Regret This Decision:Electrocute and drug yourself at the same time. I reccomend drugging first. You dont have to complete a surgery to get this achievement.And They Said It Was Impossible!:Do the same as above, but complete surgery. Do these 2 things in 20 seconds, then do surgery. This is VERY confusing, but there is no time limit, so take your time.Butter Fingers:Lose all the organs in the ambulance heart surgery out the back of the ambulance.
Randomly, (I think!) the doors of the van open. When this happens, throw the lungs, stomach, liver, damaged heart but NOT the oesophagus (tube) out. Looks pretty hilarious when you see them go on the road. Poor drivers get a lung to the windscreen.:(. What Have I Done??:Be really bad at surgery and kill the patient in 15 seconds.
The easiest way to do this is go on the brain surgery, grab the drill, then lodge it drill-bit first into his skull. Instant death, looks pretty cool as blood splatters everywhere on the death screen. Poor Bob.Hammer Time:Use the hammer to loose a total of 50,000 blood. This is about 9-10 surgeries of you murdering Bob with only a hammer.Mother Hen:Keep every tool in the ambulance on a surgery.
I did this without realising, not that hard. If its really hard for you, try put the common tools that fall out the back of the van into the cupboard at the left, where the oxygen tank is.Keyhole Surgery:This was my LAST achievement, I had NO idea how to do this for ages. On the heart transplant, remove the ribcage entirely. Use the circular saw, cut the ribs quite close to the edge of his body, and take out the ribs. I felt like a real idiot not knowing how to do this. This CAN be done on the Heavy in the TF2 update, and it appears to be the easiest way, by hitting the middle of the Heavys chest with the wrench.Practically Licensed:Simple.
Complete all surgeries including the secret one at the end. NOTE: You may be able to unlock this by only doing the TF2 mission, but this could be a bug.I Should Never Have Doubted Myself:Get an A on a surgery. My first was the kindey ambulance. Ratings are based on blood loss, and it seems if you dont go below 5100ml (losing 500ml of blood) youll get an A, but it varies. (I got an A on heart from having 4600ml.)Best Surgeon In The World:Not my endgame achivement, but its supposed to be I guess.
Once you get 1 A, the others come soon after. You feel pro getting this! This DOES include the secret mission (after the TF2 update.) Also, if it does not come up for you, try doing the TF2 mission as well.Like A Wet Paper Towel:I got confused with this one. Its actually really easy. Grab the new heart on the heart surgery, then throw it LEFT off the table.I'm Sure He'll Live:Not as hard as you think. Complete a surgery with less than 10ml of blood.
Any surgery works. I would almost complete the surgery (so you only have to throw the brain/heart/kidneys in, then make him loose loads of blood, then when he's about 50ml-100ml, prod him with the green needle. Keep prodding him so he dosnt start losing blood, but blood level goes down. Then when below 10, throw the transplant in!Like An Animal:Throw everything on the floor on the brain transplant. I see people confused on this one. Its easy, just grab all the tools, beakers, EVERYTHING!
And throw them on the ground. Try not to spill those tounge depressors everywhere.Vworrrp Vworrrp:Doctor Who reference! A time lord has 2 hearts. Throw the new heart in while the damaged heart in still in the body, attached (without cutting the arteries.)The Beat Of Your Heart:Make Bob the new Soundwave, instead of replacing his heart with the donors heart, replace it with the radio.Frikkin' Lasers:Complete a surgery using only the laser. The brain is the easiest.
It dosnt matter if you drop the laser, just dont pick anything else up except the brains. Try not to laser the brain, or he will loose lots of blood very quickly, and the needle may not save him in time. Additionally, picking up the needle results in loss of the achievement.Doctor Doctor, Give Me The News:Answer the phone. While in main menu, wait for the phone to ring. Instead of punching it off the table, pick it up and listen to Nigels friends complain about his costume, his dad washing his bloodied jeans, his landlord complaining about his bloodied boots.
HIS KEBAB STORE COMPLAINING ABOUT THE STOMACH MEAT. AFTER YOU GET THIS, THROW THE PHONE ON THE FLOOR, NEVER ANSWER IT AGAIN. EVER.Nigel The Secretary:Do Secretary stuff.
Draw on the notepad using a pen. (If you want to draw stuff better, try getting the pen in a downwards position.)Go For The Optics!:Grab the laser on the brain transplant, and laser his eyes. Takes a bit of moving around on both eyes.10 Megabytes Of Raw Data:Complete all operations, youll get some floppy disks.Spaaaaaace:Go to space!
Insert the black '???' Disk into the disk tray. Hard surgery!
This is the 'secret' mission.Don't Be Such A Baby, Ribs Grow Back!:Completely ruin the ribs. Grab hammer, smash everything, right to their little nubs of bone.About As Politically Correct As Fur:Get the large intestine and put it around Bobs neck to give him a fashion sense. Takes a bit of wiggling it around.There Is Nothing More To Teach.:Get all achievements! Do everything! Valve Actually Let Us Do This?:Successfully use the VHS tape. Take the tape of the very right of the menu screen and push it into the slot, like a floppy disk.Let's Go Practice Medicine:Perform an uber heart transplant.
This is quite a tricky one, but if you've seen 'Meet the Medic' video, you'll have an idea of what to do. To do this, rip open the ribcage, take out lungs and liver, cut arteries with the small knives, take out the heart and throw it away. Then open the fridge at the back right (an update made the fridge harder to open. You have to grab the handle and pull it left, and the fridge door comes loose.), and take the 'mega baboon' (bigger) heart.
Place it on the table to the right, where there is a little metal thing with wires and 3 prongs. Stick that into the heart, so you can pick the heart up by grabbing the metal thing. Then, go to the joystick, and aim the health ray somwhere where you can reach. Then hold the heart + metal thing under the ray so it makes a 'WOOOPWOPWOP' noise.
After a bit, the screen with go saturated a bit, and the medic will say something. Now put the heart into the chest cavity, and aim the health ray - using the joystick - at the chest cavity, (pull it down to make it go up) so it glows, and the skin heals back.
After the skin heals back, you are done!The Sound Of Progress My Friend!:Explode a heart. When you have cut the old heart loose, stick the metal thing into that heart, and put it under the health ray. It will explode. You can also use the Loch Ness Hamster heart in the fridge.Archimedes!:Hit Archimedes with a heart. Take the old heart, or one from the fridge, and hit Archimedes, the bird, who is directly at the back centre. You will have to throw it, but it is and easy target.
Tip: Release the heart facing upwards, to give it direction, and let go as soon as you reach the boundry, where the hand cannot go any further.Should I Be Awake For This?:Perform an uber heart transplant losing less than 1000ml of blood (to 4600ml). Not that much harder than the normal. The key is not to make him loose blood.
I used the spanner/wrench to break open his ribcage, but the statue is very good at breaking the whole thing. It doesn't need much breaking to get in or put the heart in. Also be careful with the knife when cutting arteries, try not to hit anything other than them. Also ensure no wild tools bash into him, like the bat, or he will loose blood.That's How I Lost My Medical License:Perform an uber heart transplant in under 2 minutes 30 seconds.
Again, not much harder than the first. Try to really smash open the ribs, I preferably use the spanner/wrench, but the statue or bomb works well too. The main time waster is the end, healing the skin back. You need to aim the ray as close to the centre as possible, then leave the joystick so it stays there.
A lot of speed runs come with practice. You can also knock some time off by putting the heart + metal prong thing directly into the chest cavity before charging it with the medi-ray, then aim the gun at the chest. This way, you dont have to spend time aiming the ray as much.
The achievements added 25th September 2013, including some awesome secret stuff.It's In! It's In I Tell You!:You need to 'put' the heart in after the patient has died during the normal heart transplant. Its quite simple. Take everything out the chest, lungs, stomach, old heart, and everything else.
Then you need to give him a high blood loss. Do this by slapping him with a hammer or the blue syringe.
Then grab the new heart and hold it above where it should go to complete the surgery. When the patient dies of blood loss, your hand will dissappear, letting the heart drop in slow motion.
King exit gallery. Wait for it to hit the cavity, and you should get the achievement.Nothing But Skull:You have to throw the brain into the skull and complete a surgery on normal brain transplant. This is quite the difficult one. Destroy as much of the skull as you can and take out the brain.
Grab the new one and face it downwards, then position the hand as far as you can back and in front of the skull. Then flick your hand up, giving the right angle and power to throw the brain into the cavity. Takes a bit of practice, try watching the video for reference.Let's See That Sick Filth Again:Take the spoon to the right on kidney transplant (normal) (This spoon is positioned right for optimal spoon flipping.) and grab it by the handle.
Turn the hand so the palm faces the roof, and you can see the spoon. You have to flick you hand up and let go, so the spoon flies into the air and spins. When it has spun 180 degrees (so the end of the spoon faces you) you have to grab it. I reccommend watching the video for this, it is hard to explain writing.Call Trisha:She's a nice lady. Use the phone in the main screen by taking the actual phone out of the socket (it should make a noise). Pressing buttons is the hard part.
Use only your index finger (A, W E and Space) and tilt your hand slightly, so you can see the number you are going to press and your finger. Then type in her number.
For those unware, it is 50, these numbers were found from secrets in each level, e.g. Poking the blood bag, on the road.Hah We Probably Made You Do It Again:Perform a heart transplant in space. Quite the same as the normal surgery, only stuff flies around everywhere. Make sure the transplant heart stays in or near the box, otherwise it may be lost. Also keep the green syringe safe, just in case.No Time To Admire The View:Complete the space heart transplant in under 1 minute 40 seconds. This is about the same diffuculty as normal, it helps that the bones and organs fly out and dont bother you again. Once again, use the drill to obliterate the right side, only taking out the right lung, stomach and oesophagus.
Scalpals are hard to grab in space in the right position, so keep one close by.In Space, No One Can Hear You Bleed:Complete the space heart transplant losing no less than 400ml of blood (to 5200ml). Again, similar difficulty. With all the stuff flying around, watch out for rouge sharp thingys bashing to Bob.
Go careful, use the circular saw, and keep the green syringe nearby.Zero G Kidney:Perform a double kidney transplant in space. Similar to heart transplant, the surgery is easier in the sense that all the stuff flies out, but harder in the sense that everything is everywhere. Keep the kidney cutter nearby and on the table, it is the key to success, albeit, it is hard to grab in the right position.Stomach O'Clock:Perform the space kidney transplant in under 2 minutes. Go nuts with that kidney cutter, as long as you know where the joints for cutting are, you'll be fine, all the stuff flies out and it is easier than the rest. (IMO) Just watch for the transplants flying about.The Surgery Of The Future:Complete the kidney space transplant losing less than 400ml of blood (to 5200ml). Use the kidnet cutter carefully this time, make sure it doesn't fly off, 'cause scalpals are your worst enemy here. Just watch for hitting any part of Bob that isn't his organs.It's Hardly Rocket Science:Perform a brain transplant in space.
As with the normal brain surgery, flopping a hammer around his head should clear most of the skull, then a quick slice of the brain stem and you're good to go. The brain in the container doesn't fly out much, so this is an easy surgery.Speedrun Time:Complete the space brain transplant in under a minute.
Smashy smashy hammer fun times & co. Just ragglefraggle everywhere with the hammer so all the skull is gone, pull it out and slice with scalpal. I find this very easy and fun.Precision Instrument Time:Complete the brain space transplant losing less than 600ml of blood (to 5000ml). This one is not easy or fun.
Go gentle with the circular saw around his head, that is the hardest part. Make sure not to hit his brain or face with said saw/tool, as he will lose lots of blood. Watch for rouge flying pointy objects.Enter The Code:On the brain space transplant, in the top right corner, there is a working keypad. If you followed the problem solving required in getting the code, you'll know how fun it is. The code is 296145, found from various puzzles around the reception, including scribbling on Trishas note, Saturns orbit in years around the sun and a special VHS from calling the surgeon team from the Barnardshire general website.We're Going On An Adventure!:Take the radio into space. After entering the code on space brain transplant, grab the radio and hold it until it goes to the next sequence.????
Screw The Prime Detective:Reveal the patient from entering the code on brain space transplant. Insert the VHS from entering the code into the VHS player. Some numbers will appear.
When going onto the secret transplant, enter them into the keypad. They are 4948I Have No Idea What I'm Doing:When you have revealed the secret patient, smash all the organ tube things with the hammer quickly. You can usually chain them if you go fast. Make sure the hammer is on the inside when smashing (so you tilt it when going to the right side) and it will be much easier.Best Surgeon In The Universe:You must complete all alien secret transplant. When entering the code to reveal the patient, you MUST look at what it says.
The name depends on what you have to transplant. They are as follows:. Cube Trangrifier: The black cube with a blue light on it, deep in the body.
This electricutes (reverses controls) when you cut the wire. Robbaloraz: The intestine-like thing, by the stomachy thing. Pewdball: The ball of red-black stuff, under the bone cage. Gobbleshaft: The strange light blue-green thing with the 6 connecters to the side of the body. I think it is a horse. It makes horse noises when cut. IMPORTANT: To get the gobbleshaft to be accepted, you MUST cut the tubes right by the gobbleshaft, not the ones close to the edge.
Gavichal: The orange thing in the top right with the light blue spikes. The spikes partially drug you when touched. Bigirspallex: The stomachy/lung thing, purply blue with light green in it.Lots of these reference youtubers who played the game. When all the transplants have been done (for each organ) you get the achievement. Here's a few things I've seen/been told playing this game, which may affect how you get your achievements.1.
When writing this guide, I had an older work PC, which averaged 30FPS or less. I got a new gaming PC, where my FPS is increased by loads. On the older PC, the liver on the kidney transplant was MUCH harder to get out than on the new PC. The new PC requires only to grab the liver and pull it out. The older PC required poking it around to get it out.
Just something to note if you have an old PC and cannot get the liver out.2. A comment tells me people with older keyboards have what is called 'Ghosting.' Ghosting is where multiple keys cannot be pressed at the same time, usually over 3, simultaniously. I checked Microsoft's virtual ghosting keyboard, and AWER SPACE seemed to work fine, but if you have a different keyboard type (like AZERTY) or have binded your keys to different ones (not AWER) then this may affect you. If AWER dosn't work for you, this may still be the case. There is no real fix for this, other than getting a new keyboard (even a cheap one) and getting some achievements such as the finger gesture ones may be impossible. Normal gameplay is still possible, as W and SPACE are sufficient to pick up most objects.3.
Most speed or blood loss achievements come with practice, and there is only a few tricks to help solve them. This guide gives you as many tips as I have seen or done, but the achievements themselves are up to you, and they best way you can get them is to practice, and become a pro!
doi: 10.1097/00000658-200210000-00008
PMID: 12368674
This article has been cited by other articles in PMC.
AbstractObjective
To demonstrate that virtual reality (VR) training transfers technical skills to the operating room (OR) environment.
Summary Background Data
The use of VR surgical simulation to train skills and reduce error risk in the OR has never been demonstrated in a prospective, randomized, blinded study.
Methods
Sixteen surgical residents (PGY 1–4) had baseline psychomotor abilities assessed, then were randomized to either VR training (MIST VR simulator diathermy task) until expert criterion levels established by experienced laparoscopists were achieved (n = 8), or control non-VR-trained (n = 8). All subjects performed laparoscopic cholecystectomy with an attending surgeon blinded to training status. Videotapes of gallbladder dissection were reviewed independently by two investigators blinded to subject identity and training, and scored for eight predefined errors for each procedure minute (interrater reliability of error assessment r > 0.80).
Results
No differences in baseline assessments were found between groups. Gallbladder dissection was 29% faster for VR-trained residents. Non-VR-trained residents were nine times more likely to transiently fail to make progress (P < .007, Mann-Whitney test) and five times more likely to injure the gallbladder or burn nontarget tissue (chi-square = 4.27, P < .04). Mean errors were six times less likely to occur in the VR-trained group (1.19 vs. 7.38 errors per case;P < .008, Mann-Whitney test).
Conclusions
The use of VR surgical simulation to reach specific target criteria significantly improved the OR performance of residents during laparoscopic cholecystectomy. This validation of transfer of training skills from VR to OR sets the stage for more sophisticated uses of VR in assessment, training, error reduction, and certification of surgeons.
The introduction of laparoscopic cholecystectomy and the subsequent rapid growth of minimal access surgery (MAS) have challenged conventional systems for surgical training and establishment of competency. After 1989, as MAS became more commonly practiced, it became clear that the laparoscopic approach was associated with a significantly higher rate of complications, particularly during surgeons’ early experience with these procedures. The underlying causes of these developments were complex but ultimately related to inadequate training of the skills necessary to overcome the psychomotor hurdles imposed by videoscopic interface. When higher complication rates with MAS were scientifically validated, surgeons set about defining more structured training methods, such as the Wolfson Minimal Access Training Units in the United Kingdom. However, laparoscopic surgical training has for the most part remained relatively unstructured and patterned on the same mentor–trainee model that served surgical training objectives throughout the last century. At the onset of the 21st century, the surgical education establishment is searching for new and innovative training tools that match the sophistication of the new operative methods.
Concurrent with the growth of MAS, separate developments have brought considerable focus on the issue of errors in medicine. The “Bristol Case”4 in the U.K. and the “To Err is Human”5 report published by the Institute of Medicine in the United States suggested that better training and objective assessment would be key strategies in attaining the goal of reduced medical errors. Surgeons were already sensitive to these issues and have accepted the idea that new and better evidence-based training is necessary and achievable.
Drawing on the successful paradigm of flight simulation, Satava first proposed training surgical skills in virtual reality (VR) nearly a decade ago. Since that time, with the advancement of desktop computing power, practical and commercially available VR-based surgical simulators and trainers have been developed. At Queen’s University, Belfast, and at Yale University such systems have been employed for training and assessment of surgical skills. 7–9 Results from both centers show that VR training results in technical skills acquisition at least as good as, if not better than, programs that employ conventional box trainers. 10,11
The most important goal of any training method is to increase the level of skill that can be brought to bear on a clinical situation, but to date no studies have established a clear benefit of VR training that transfers to surgeon skill measured in the operating room (OR). Our current study, a component of the program project “VR to OR,” was undertaken to determine whether training on VR in the skills laboratory generalizes to the clinical OR. A commonly performed laparoscopic procedure was selected for examination, along with a VR trainer task that was felt to most effectively train the desired operative skill.
METHODS
Sixteen surgical residents (11 male, 5 female) in postgraduate year (PGY) 1 to 4 in the Yale University School of Medicine Department of Surgery participated in this study. All study participants were randomly assigned to either a study group that would receive VR training in addition to the standard programmatic training (ST) appropriate for PGY level, or a control group that would receive ST only. Participants were stratified by PGY. All residents in both groups completed a series of previously validated tests to assess fundamental abilities. Visuospatial assessment included the pencil and paper Card Rotation, Cube Comparison, and Map Plan tests. 12 Perceptual ability (reconstruction of 3-D from 2-D images) was assessed on a laptop computer with the Pictorial Surface Orientation test (PicSOr). Psychomotor ability was assessed with the Minimally Invasive Surgical Trainer-Virtual Reality (MIST VR) system (Mentice AB, Gothenburg, Sweden) with all tasks set at medium level of difficulty.
Apparatus
The MIST VR system (Frameset v. 1.2) was run on a desktop PC (400-MHz Pentium II, 64-Mb RAM) with tasks viewed on a 17-inch CRT monitor positioned at operator eye level. The video subsystem employed (Matrox Mystique, 8-MB SDRAM) delivered a frame rate of approximately 15 frames per second, permitting near-real-time translation of instrument movements to the video screen. The laparoscopic interface input device (Immersion Corporation, San Jose, CA) consisted of two laparoscopic instruments at a comfortable surgical height relative to the operator, mounted in a frame by position-sensing gimbals that provided six degrees of freedom, as well as a foot pedal to activate simulated electrosurgery instruments. With this system, a 3-D “box” on the computer screen represents an accurately scaled operating space. Targets appear within the operating space according to the specific skill task selected and can be grasped and manipulated with virtual instruments (Fig. 1). Each of the different tasks is recorded exactly as performed and can be accurately and reliably assessed.
Figure 1. MIST VR screen appearance on “Manipulate and Diathermy” task. The sphere, which must be precisely positioned within a virtual cube, presents a target for the L-hook electrosurgery instrument. Objects may be positioned anywhere within the defined operating space.
Training
Four attending surgeons, all with extensive prior experience with laparoscopic procedures, completed 10 trials on the MIST VR “Manipulate and Diathermy” task (see Fig. 1) at the “Difficult” level to establish the performance criterion levels (mean error score = 50, mean economy of diathermy score = 2). The training goal for residents in the VR group was to perform the same task equally well with both hands on two consecutive trials at the criterion levels set by the experienced surgeons. Training sessions lasted approximately 1 hour. Training was always supervised by one of the authors (A.G.G. or N.E.S.), and explicit attention was paid to error reduction and economy of diathermy.
Operative Procedures
All residents performed laparoscopic cholecystectomy with one of surgeon-investigators, who were blinded to the subject’s training status. Before procedures, all were asked to view a short training video demonstrating optimal performance of excision of the gallbladder from the liver using a hook-type monopolar electrosurgical instrument. This video defined specific deviations from optimal performance that would be considered errors. After the viewing, all residents were given an eight-question multiple-choice examination that tested recognition of these errors. During surgery, after division of the carefully identified cystic structures, residents were asked to perform the gallbladder excision using a standardized two-handed method. This phase of the procedure was video-recorded with voice audio by the attending surgeon describing any interventions (attending takeover of one or both instruments). Procedures with attending takeover were flagged for examination of audio.
Error Definition
During unfettered review of archived videotapes of laparoscopic cholecystectomy, potential measures of surgical performance were collated and discussed by the four surgeon-investigators and one behavioral scientist involved in the study. From this list, eight events associated with the excisional phase of the procedure were defined as errors and chosen as the study measurements (Table 1). These measurements excluded any inferences that were not directly observable. All of the events were explicitly defined to facilitate interrater agreement. Clear guidance was given as to when an event was judged to have or have not occurred. The length of time of the gallbladder excision phase was also determined. Timing of length of procedure started with first contact of the electrosurgical instrument with tissue and ended when the last attachment of the gallbladder to liver was divided.
Interrater Reliability Assessment
Each procedural video was viewed without audio by two surgeon-investigators blinded to operating team members. The gallbladder excision phase of the procedure was scored on a minute-by-minute basis using a scoring matrix (see Fig. 1) that enabled the observers to record whether an error had or had not occurred during each 60-second period. Errors were recorded using fixed-interval time span sampling (one-zero sampling) described by Martin and Bateson, 14 where a single error event is scored irrespective of how many times during the 1-minute defined period it occurred. Attending takeover events were scored afterward based on review of the flagged videos. Interobserver agreement was determined as described by Kazdin for interval assessments according to the equation: agreements/(agreements + disagreements) times 100. 15
Data are expressed as mean ± standard error. Statistical comparisons were performed by chi-square analysis, analysis of variance (ANOVA), and Mann-Whitney test (SPSS, Chicago, IL), with statistical significance taken at the P < .05 level.
RESULTS
There were no significant differences in any of the initial battery of assessment tests noted between the VR and ST groups (Fig. 2). All residents randomized to the VR group successfully achieved the required criterion levels of performance in three to eight training sessions. All residents in both groups successfully completed the dissection of the gallbladder from the liver bed. The interrater reliability for the assessment of residents’ operative performance during video reviews was 91 ± 4% (range 84–100%).
Fig. 2. Results of fundamental abilities assessment. No significant differences were noted in visuospatial, perceptual, or psychomotor abilities between subjects randomized to ST and VR groups when assessed before the training phase of the study.
The duration of the dissection for the VR-trained group was 29% less than in the ST group, although this difference did not achieve statistical significance (Fig. 3). Gallbladder injury and burn of nontarget tissue errors were five times more likely to occur in the ST group than in the VR group (one of each error in VR residents as compared to five of each error in the ST residents). Separate comparisons between the groups for these errors demonstrated statistical significance in both cases (chi square 4.27, df = 1, P < .039). ST residents were nine times more likely to be scored as lack of progress, with mean number of lack of progress errors per case of 0.25 versus 2.19 (VR vs. ST groups, respectively; Mann-Whitney, Z = −2.677, P < .008). There were no tearing tissue errors or noncontact cautery errors in either group. There was one liver injury, three dissection incorrect plane, and six attending surgeon takeover errors scored, all in the ST group. In all error categories except liver injury (one error in VR group) and tearing tissue (no errors either group), more errors were observed in the ST group than in the VR group (Fig. 4). The ST group made six times as many errors as the VR group (Fig. 5), with four times the variability in the performance of the VR residents as indicated by standard errors. The mean number of scored errors per procedure was significantly greater in the ST than in the VR group (1.19 vs. 7.38, Z = −2.76, P < .006, Mann-Whitney test).
Figure 3. Mean duration of operative procedure for the VR and ST groups.
Figure 4. Total error number for each error type. LOP, lack of progress; GBI, gallbladder injury; LI, liver injury; intraperitoneal, incorrect plane of dissection; BNT, burn nontarget tissue; TT, tearing tissue; IOV, instrument out of view; AT, attending takeover. In all error categories except LI and TT, a greater number of errors were observed in the ST group than in the VR group.
Figure 5. Sakura space game unconcerned. Total number of errors scored per procedure for VR and ST groups. The mean number of errors per procedure was significantly greater in the ST group than in the VR group (P < .006).
DISCUSSION
The results of this study demonstrate that it is feasible to train operative skills in virtual reality in surgical trainees without extensive prior MAS experience. Residents who trained on MIST VR made fewer errors, were less likely to injure the gallbladder and burn nontarget tissue, and were more likely to make steady progress throughout the procedure. During VR training it was made clear to residents that speed was not a major training parameter. Instead, training emphasized safe and economical use of electrosurgery instruments and positioning of “tissue” with the nondissecting hand. Completion of the training phase was carefully defined based on objective performance criteria established in advance by experienced laparoscopic surgeons. In the planning phase of the study, it was uncertain whether these criterion levels were set too high, but pilot testing demonstrated that these levels could be attained by residents. This is an important point since if the criterion level were set too high, study participants would not be able to reach it. These targeted performance levels may have contributed to the consistent performance demonstrated by the VR-trained group in the OR phase of the study. The requirement that explicit performance criterion levels be reached on two consecutive trials made it unlikely that the resident could achieve it by chance. The performance criterion level established by laparoscopic surgeons at Yale University will need to be validated by the larger surgical community to determine whether they are appropriate measurements and levels to reflect “expert” performance.
No matter how sophisticated laboratory assessment and training methods become, their relationship to OR performance must be established. Our operative assessment methodology was designed to measure observable surgical performance. No inferences were drawn about why the resident performed in a particular way. Global ratings of resident performance and Likert-type scales were avoided in favor of the fixed-interval time span sampling method that identified the presence or absence of predefined error events. This emphasis on observable events resulted in interrater reliability levels that remained above 0.8 throughout the study, with effective blinding of observers to study participant training status. Prior efforts to quantify performance during laparoscopic cholecystectomy have examined similar errors, but with a more global view of the procedure. Although clearly feasible and reliable, this methodology was somewhat time-consuming during both the training and scoring phases.
For the purposes of this investigation, we have chosen a simple operative task that emphasizes technical skills. “Errors” in operative technique were defined as specific events that represented significant deviations from optimal performance, without linking these events to adverse outcomes or proximate causes. The identification and measurement of these errors permitted assessment of the effectiveness of VR training specifically intended to reduce their incidence. The simplicity of the operative procedure aided in the attainment of this study goal. However, competency comprises disparate cognitive and manual skills elements that do not necessarily lend themselves to unified testing. Anticipating that VR training will rapidly become more varied and realistic, more sophisticated methods of isolating and measuring specific skills in the OR are still needed. We envision the extension of these training tools to other procedures with the aim of eliminating behaviors that lead to adverse clinical outcomes.
The validation of VR training in training operative skills marks a turning point in surgical education. The potential exists to train a resident to a high level of objectively measured skill before he or she is permitted to operate on a patient. VR trainers and simulators offer the advantage of allowing as much training as is required to achieve the training goal. During our study, an investigator observed and instructed the residents during training exercises in order to validate the system. In the immediate future surgical trainees will be able to train whenever they choose, with their performance continuously assessed by the simulator until proficiency in the selected task is attained. With proper software, computer mentoring of the training task is also feasible. The implication is that the surgical education process will soon have the ability to “train out” the learning curve for technical skills on a simulator, rather than on patients; and that a high level of mentoring can be provided without consuming an inordinate amount of a supervising surgeon’s time. VR simulators maintain a log of performance over time, providing an automatic quality assurance tool for objectively assessing the advancement of an individual’s basic technical skills for the program director. It must be emphasized that many more skills are incorporated into the technical training of a surgeon (including the cognitive skills of anatomical recognition, decision making, alternate planning, and so forth), and that the simulators are but one part that can contribute to the overall improvement of performance and assessment of proficiency. Nevertheless, our study validates for the first time the role of VR training on the ability of surgical residents to perform an operative procedure with an improved and, arguably, safer performance. Our findings therefore support the introduction of VR training into surgical education programs.
DISCUSSION
Dr. Carlos A. Pellegrini (Seattle, WA): The authors of this very important paper tested, in a randomized, double-blind study, the hypothesis that virtual reality surgical simulation training would improve operating room performance. The objective assessment of the laparoscopic cholecystectomy showed that the VR training definitely improved performance when compared to a group of residents trained by traditional means.
A study by our own group in which residents were trained using artificial tissue-like materials shows that these exercises significantly enhanced performance and decreased errors when doing a cholecystectomy in a pig by the residents that were trained this way. Our system allowed us to determine performance objectively at every step of the training phase.
Could you tell us about the individual differences among the residents at the starting time? We found significant differences at the beginning of the training phase, and very little difference, with everybody achieving a performance within 10% of each other, at the end of the training phase.
Was any individual in your study excluded because at the beginning they did not achieve whatever performance levels you have when you take this and other tests? And most importantly, did anyone fail to meet the preset criteria that you had established? Was anybody excluded from this study?
However important these details may be, I would like to make sure that we do not miss the forest for the trees. The real contribution of this presentation, as I see it, is the demonstration that today, using computer simulation and virtual reality environments, we can teach residents skills that in the past we could only do in the operating room or at best in the animal laboratories. Virtual reality simulators allow students of surgery to practice as many times as they need to, which we found to be a very important element of learning. I think that this would definitely improve the nature of the learning experience, and, most definitely, the quality of life of the resident.
One of the things that we have done is to bring to our laboratories medical students. In fact, we studied fourth-year medical students. I believe that if we want to reverse the trend away from surgery, as President Debas so eloquently described yesterday, we should expose our students to these environments early on in their careers. And herein, I think, lies the strength of the study. Indeed, it is surgeons that have developed and are at the forefront of virtual reality simulation. And since once created, this environment can be modified for other tasks, I believe that surgeons are in a unique position to offer to train medical students in basic skills. Early exposure to these individuals, establishing relationships and friendship at an early stage of medical student careers, I think will have, or may have, a profound effect on their ultimate career choice. Perhaps the authors may wish to comment on this, a less obvious but I think a much more important aspect of their work.
Dr. Neal E. Seymour (New Haven, CT): With regard to your first question, Dr. Pellegrini, none of the subjects were excluded based on the performance criteria levels that we established before they trained. We initially had some concerns that by having experienced laparoscopic surgeons use the MIST-VR to establish a performance benchmark, a new class of difficulty for the task would be created. We did not wish to set a target performance criterion level that could not be achieved by surgical residents at all PGY levels of training. During an early phase of the development of our methods, we tested the ability of residents who were not randomized for the actual study to reach those criteria and levels and found that they could, although there was significant variability in the amount of training that was required to accomplish this. Generally, more senior residents required less training, although the small “n” value does not permit more specific comment on construct validity. There were some differences noted among individuals in the study which I have not presented here today. These pertain to gender-specific performance with regard to the rate and consistency in skills acquisition. Ultimately, the achievement of performance criteria was not a problem for any of the subjects in this study and no one was excluded on that basis.
I absolutely agree with you on the value of VR as a component of a fundamental skills acquisition program, even at the present level of technology of widely available virtual reality simulators and trainers. These devices can, in conjunction with an appropriate curriculum, provide a means of both training and assessing performance. It is not to my mind a replacement for mechanical box trainers and other training techniques, particularly if one examines more complex tasks which currently cannot be achieved in virtual reality. Suturing and knot-tying are VR tasks in development that most readily come to mind in this regard. Simulation of these tasks is a major goal for the engineers and software developers who are currently working in this area. Until this goal is achieved, VR will be extremely valuable for basic skills but somewhat limited for advanced skills acquisition.
However, having said that, direct prospective comparison of box trainers tasks and the MIST-VR in basic skills acquisition anticipatory to the development of laparoscopic suturing and knot-tying abilities have shown that the VR simulator prepares trainees equally well if not better than a box trainer. The training used with the box trainer in that study consisted of the Rosser drills, a well-validated method of preparing trainees and students to do laparoscopic suturing and knot-tying. Preliminary studies like this prompted us to focus on VR as a means of acquiring basic skills in preparation for the OR.
Students are certainly able participants in any VR basic skills acquisition program, and they stand to benefit in a number of ways. Seeing this technology may, in fact, influence a decision to pursue a career in surgery. However, our immediate focus has been on surgical trainees and on giving them the skills they need to perform laparoscopic surgery at a higher level when they enter the operating room.
Dr Ajit K. Sachdeva (Chicago, IL): I believe this a landmark study, as Dr. Pellegrini has mentioned. The study has demonstrated, through a very elegant study design, the transfer of psychomotor skills acquired in a virtual setting to the real environment. Thus, the predictive validity of the educational intervention has been demonstrated. Also, the measurement approach used by the authors is quite innovative. In the past, evaluations conducted by other investigators have involved the use of global ratings and, prior to that, checklists. The objective evaluation of errors rather than the evaluation of the psychomotor skills using global ratings or checklists is a move in the right direction. I have a number of questions for you, Dr. Seymour. First, although the cohort of residents was small, did you see any trends by level of learner? Was there a difference in the transfer of skills at the different levels of residents, from years 1 through 4? Second, what was the time interval between the completion of training in the virtual environment and evaluation of skills in the operating room? My third question relates to the second. If the time interval was long, was there any operative experience that might have contributed to the acquisition of the psychomotor skills, and thus have contaminated the results? Finally, what are your plans for further dissemination and validation of your approach? We certainly need larger data sets to further validate your findings, study other types of validity, and assess the generalizability of your approch.
Dr. Neal E. Seymour (New Haven, CT): I appreciate your comment on the predictive validity of the study. We obviously designed our study with predictive validity in mind. We were determined to do our assessment of operative performance without using global ratings and maintaining a focus on errors because we felt that the study strategies would maximize the sensitivity in demonstrating skills transfer. In answer to your first question which pertains to the number of residents and level of training, I believe you were referring to the issue of construct validity. As I pointed out earlier, our study was not designed to test construct validity which has been demonstrated very clearly for the MIST-VR system in the past by a number of investigators including Anthony Gallagher, one of the investigators in the current study. We could see differences between residents at different PGY levels in the number of training sessions it took to achieve performance criterion levels. There were no statistically significant trends in that data, and I have not presented because of, as you rightly pointed out, the small size of the study.
The time interval between completion of the training and performance of the operative procedure was kept to a minimum with some variability due to the vagaries of operative scheduling. Residents were able to do a laparoscopic cholecystectomy with one of the surgeon-investigators within two weeks of the completion of training. Although I think that pushing the operative procedure out to two weeks introduced some question that there might be time-dependent attenuation of the effect of the training, that proved not to be the case. As to our future work in this area, we have shifted our focus to higher end, high fidelity simulators and are examining more sophisticated operative tasks such as clip application and tissue division in laparoscopic cholecystectomy. It is fair to say that these more advanced simulators are much more interesting and exciting for participants to use. This relates to the perception of a more sophisticated task, and the face validity of manipulating recognizable tissue and anatomic structures. The problems of devising the appropriate metrics for the simulators are being solved at present time. As this work evolves, I believe we are going to obtain some very interesting data with these high fidelity simulators as well.
Dr. Johnathan L. Meakins (Montreal, Quebec, Canada): I second the remarks of Dr. Pellegrini. It is noted that OR time is so precious and expensive that it can’t actually be used for practice; whereas, on the other hand, there is an old joke, the punchline of which is, “The way to Carnegie Hall is practice, man, practice.” So that is a part of what has been demonstrated.
Cost issues (i.e., OR time, surgeon teaching time, etc.) need to be integrated with the cost of the simulators, how we create the software and how it gets disseminated and need to be integrated into use. These two cost issues need integration with the ways in which we as surgical educators reframe residency programs to deal with modern constraints. I just will mention the 80-hour workweek as an example. There is, however, a second constituency who may well need this kind of training. That is the surgeon in practice who has to deal with a new technique, a new technology, or a new operation, and needs to learn that in an appropriate way. What is the cost and the time required to create the kind of simulator model that you have got so that it might be applied to the second constituency; that is, those of who need to learn how to do something brand new?
Dr. Neal E. Seymour (New Haven, CT): With regard to the surgeon in practice, I think that we are waiting on the sort of simulations that train very, very specific procedures rather than focus on acquisition of basic skills, although certainly there is still probably plenty of room for basic skills improvement in that target group of surgeons who might want to increase laparoscopic skills. Getting this technology out to surgeons in practice presents an entirely different set of problems that we are currently dealing with. As the machines become more advanced and more available, there will be increased opportunities for community surgeons to have access to simulators to hone skills. We have not worked out the details of how best to achieve that, but it is certainly something to give consideration to.
I am probably not the best person to address the issue of cost of VR training, although I am aware of the considerable cost of the machines that we are using. It is not clear who is best able to pay the development costs of more advanced medical simulation technology or how to generate interest in this sort of endeavor among venture capitalists. I think the fundamental question boils down to who pays for surgical education. In the case of flight simulators, military simulators, and business simulators, it is quite obvious where the benefits lie and intense investment has produced machines that are light years ahead of what I have shown you, and what we currently use today. Again, I think that sorting out how to get money into surgical education is the fundamental problem. Simulators will certainly be a component of the educational process, but producing the best possible simulators is going to take dollars.
Dr. Leslie H. Blumgart (New York, NY): Three brief questions. Firstly, these operations in your study were performed under the supervision of an attending surgeon. Was it the same attending surgeon throughout? Or could the results have been influenced by different comments from the attending surgeon in the two groups? Secondly, can you use these techniques to teach judgment? For instance, in cholecystectomy, can you, using these virtual reality approaches, teach the surgeon when to convert to an open operation? Finally, can virtual reality be used to train surgeons to do operations which are not necessarily approachable by minimally invasive methods?
Dr. Neal E. Seymour (New Haven, CT): The four attending surgeons who participated in this study did so because of their interest in laparoscopic surgical training. We had a very, very clear protocol which addressed issues of surgeon behavior in the OR, emphasizing what behaviors would and would not be appropriate for the study. Certainly, patient safety was the major concern. In the case of a resident who was not performing the necessary task appropriately, and who was not responding to verbal instructions, would have one or both instruments taken away by the attending. We regarded such an event as an error and as one of the study metrics. The threshold of individuals to intervene is inevitably going to very variable however, we went to great lengths to try to preserve some uniformity of behavior based on preliminary meetings, discussion, establishment of appropriate OR behaviors, and I think to a very great extent we achieved that. But your question is a difficult one to answer and a difficult problem to test.
Simulators can teach judgment. There are many other simulator paradigms where improved judgment is the major goal of doing simulations. This particular simulator, MIST-VR, is not designed to teach surgical judgment. Another surgical simulator, the sinuscopic simulator currently in use, does overlays of anatomic information and shows on a teacher-determined basis what anatomy is revealed to the participant on the simulator, and teaches decision-making based on a continuous, dynamic education process. Rather than doing a terminal phase instruction, this is real-time instruction were anatomic information can be presented to a person so that their judgment will be shown to be adequate or inadequate, as determined by the clinical situation. So, yes, judgment should be topped by simulators and in the future will be taught by simulators with the appropriate curriculum goals in mind.
Footnotes
Supported with a grant from the Fulbright Distinguished Scholar Program (A.G.G.).
Presented at the 122nd Annual Meeting of the American Surgical Association, April 24–27, 2002, The Homestead, Hot Springs, Virginia.
Correspondence: Neal E. Seymour, MD, Department of Surgery, Yale University School of Medicine, TMP 202, 330 Cedar Street, New Haven, CT 06520-8062.
E-mail: [email protected]
Accepted for publication April 24, 2002.
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