Okay seriously this one HAS to be some kind of elaborate inside joke about...she is going to wildly guess a webcomic that she hasn't read but that apparently three random hematology experts are all really into??? Because, uh, ""supervillain supervolcano serum"" is not a...real...drug... 

To be clear, most of the discussion prompts aren't insane troll plans! It's just that the remainder are mostly boring, many of them hours old, and they're sitting in the hypothetical discussion planning section because they were worse along some dimension than the proposals that got bounced to the actual prediction market evaluation stage.

(They haven't been cleared out entirely because, who knows, Kalorm may at some point develop rapid-onset-new-allergies to vasopressin or something! It could happen! Treatment Planning is READY. And also ready for like a dozen other things that have a 0.01% chance of happening but, like, a higher chance of happening to Kalorm than to almost any other ICU patient. Most medical experts have at some point been bored and workshopped a Really Elaborate Complicated Plan for if some very specific set of medical issues occurs, and they are proud of it and have it ready to go and can drop it with a couple of minor modifications whenever it's even vaguely relevant enough to make them look clever and generate some interesting meta during the interludes when they're not doing actual work.) 

There are also some plans that are, like, broadly sensible and Kalorm-relevant and just not doable right now, mostly because they're a larger intervention for ONE of his current problems that will trade off too hard against the fragile holding state with all his OTHER current problems. For example: they could theoretically try switching to negative pressure ventilation! It's pretty inconvenient - requires a turtle-like vest that forms a complete seal around the patient's torso so that air can be hydraulically pumped out to generate a vacuum and enough force to yank air into the patient's lungs - but Kalorm is unconscious anyway and it would completely sidestep all the intrathoracic pressure cardiac output issues! The problem is that it's super not recommended for pulmonary edema; they're relying a lot on the positive pressure, and especially the baseline post-exhalation pressure, to squish fluid back out of cells, and even with that they're still on 75% O2. 

For the lungs, they could try high frequency ventilation! The issue is that it would tank his cardiac output even worse! 

(The pulmonary specialists and the cardiac specialists have a discussion subthread which has devolved into an enormous argument! This is easily the most interesting acute case on this continent right now that involves such a complicated and fraught overlap of these specialties, not to mention at least six other organ-system subspecialties. The prediction markets are also really well-funded, so there's a monetary incentive for any relevant specialist who has some free time tonight to log on, but the novelty of it is a strong incentive of its own.) 

There's a hypothetical discussion open for an experimental system that combines positive and negative pressure ventilation and theoretically provides some of the upsides of both while mitigating the downsides, but it's currently at the "tested in rats" stage, and well-tested specialized equipment to do it in humans does not actually exist. 

There are a couple of immune-system-boosting (and a couple of specific-inflammatory-response-subpathway-suppressing) drugs that have not made it past this stage of discussion due to, also, having only been tested in rats. Kalorm's situation is pretty bad but it's not yet at the "try wildly experimental drugs and hope they work" stage. (Though it looks like one of the medical VCs is currently pitching Finnar on pulling together the funding to pay volunteers for a one-day basic human safety trial. Perhaps less because this is likely to come through in time to change Kalorm's situation much, though Kalorm could certainly benefit from it even a week or two from now, and more because it would be really cool to get this drug jumped a few stages ahead in testing via the applications of LARGE QUANTITIES OF MONEY and then, herself, make a lot of money from it.) 

More cardiac optimization proposals... 

More respiratory optimization proposals...  

How does anyone DO this????? Oh right because they probably all have like +4 thinkoomph on her. Merrin is very clearly not smart enough to be looking at the Treatment Planning backend and she's incredibly overwhelmed and this is humiliating and horrible. She resorts to skimming in search of, like, keywords that might poke whatever her brain is trying to dig up. 

She's...on reflection pretty sure it's lung-and-heart-related; she can at least filter out all the weird clever plans for hypotheticals where he starts showing signs of worsening kidney or liver failure or gut dysfunction. 

The poor GI surgeons are kind of disappointed that it doesn't look like they'll get to do anything cleverer than the valve, which was, to be fair, very clever. They're now working flat-out on a new improved version! The current one uses the expand-and-lock design that cardiac stents do - in this case, an un-lockable design so it can be removed without damaging anything, though one of the surgeons will probably need to come in and do a scope in person, the exact trigger point that "unlocks" it is fiddly. Anyway, they're hoping to get a new one that additionally has either a pressure-activated or a remote-control radio activated open-and-close function, so it can better replicate the functionality of a healthy ileocecal valve, rather than being permanently stuck open.

(It's mostly fine right now; everything coming out is liquid, and occasional colon irrigation with the motility drug solution makes sure that it's working effectively enough to keep moving things along rather than letting the stool back up. But they do want to be able to take out the rectal tube at some point - it gets in the way of physical therapy and Kalorm will almost certainly complain bitterly once he's awake - and hopefully the reflex arc will have healed by then, but it might not.) 

That is indeed very interesting and clever, but Merrin is not really the proper audience to appreciate their brilliance, it was definitely a practical solution that she's very grateful for but the details of why it's hard and required so much cleverness are going over her head, and Merrin is tired and not very smart and is going to filter it OUT so she can skim the remaining stuff. 

- oh. That's intriguing. 

It's in the section of proposals tagged as pulmonary optimization and flagged as "probably not worth the risks to other organ systems yet." 

One of the interventions that can improve oxygenation for some types of catastrophic lung damage, is to transmogrify the hospital bed into a sort of suspended cocoon and then rotate the patient until they're facedown (in the prone position). Something something it shifts around intrathoracic pressures and relieves compression on important lung sections and helps with the weird ventilation-perfusion mismatches that are common in acute respiratory distress syndrome. The initial notes indicate that the pulmonary specialists plopped this in the discussion thread at the point when they weren't yet sure what was going on with Kalorm's lungs and thought it was more likely to be inflammation-mediated acute lung injury. (And also when they weren't sure Kalorm would need to be intubated - or whether he would agree to it - and were speculating on whether Merrin could persuade him to try this instead as an intervention to avoid intubation.) 

It's less studied in pulmonary edema, which is usually downstream of a cardiac problem. Based on the large datasets that do exist, putting patients in the prone position is...mixed...on how it affects cardiac output in heart failure cases. In about 25% of patients, it helps! Sometimes a lot! In another 25% of patients it makes things worse! 50% of the time it doesn't do that much! There obviously exist clever attempts by clever researchers to create accurate predictive models of which 25% of patients would benefit, but they are not yet very good, and mostly rely on a degree of invasive sensor monitoring that no one super wants to set up on Kalorm when he's in septic shock and this unstable.

(It looks like there's a very halfhearted prediction market tied to the proposal subthread, with several different specialists contributing bets based on their slightly different models, but it's not heavily subsidized - the default liquidity assigned to preliminary markets for proposals still in the hypothetical-discussion category is not a lot - and only three people total have contributed to it. The market consensus seems to believe that Kalorm is slightly more likely than priors indicate to be a patient who benefits - it's at 35%, which is higher than 25% - but the betting is sparse enough to make that number pretty tentative.) 

The main contraindication is that, well, it's a pretty involved maneuver. It makes it more inconvenient for staff to perform additional care, and of course it's basically impossible to transport a patient like this, or perform a bedside surgical procedure, until they're rotated back and the bed is returned to its normal configuration (which is mostly automated but still takes a couple of minutes.) Even patients who benefit from it tend to become more unstable during the transition. If staff are very worried, they'll put a patient in the chest compressions vest first - since regular chest compressions are obviously impossible if a patient is suspended facedown in a cocoon, and two minutes is way too long to wait - but it's not actually great for skin and pressure sore risk to leave the vest on for hours and hours, and it adds another thing in the way of accessing the patient for any basic care. Overall, given that Kalorm's oxygenation is, like, basically tolerable lying on his back, nobody has put in a bid to bump this plan up to the next discussion subpage. 

Also, nearly all of the back-and-forth on this thread is incredibly technical and dense and full of numbers, and Merrin is tired and the math part of her brain is grumbling about every single additional number she is supposed to make sense of in context. She's managing to parse the basics, mostly, with great effort, but she's pretty grumpy about it. 

She...basically agrees that they shouldn't try it right now. She's grumpy about that too! And kind of mad at Kalorm for not being stable enough to risk it and see if it helps! Because apparently she expects it to help! Maybe! Her stupid opaque illegible intuition isn't very sure of that - if she drags her brain over rocks to force it to spit out a number for her, she would guess, like, 60%? 

Which is really different from 35%! It's incredibly frustrating that her brain is failing to provide any explicit, communicable-in-words justification for why she puts such a different number than the very qualified experts. She has a very handwavy sense that, like, the interlocking system that is Kalorm's heart and lungs is under strain - obviously - and there's some kind of positive feedback loop there, and so anything that helps his lungs will help his heart too? If she drags her brain over MORE and BIGGER and POINTIER rocks, she can eventually get as far as "maybe they'll be able to reduce the ventilator pressures, which will help his heart fill with more blood at the same heart rate" and "maybe a higher O2 sat will be good? somehow???" 

...she is too tired for this right now. It's nearly 11 pm; she's now been here for 12 hours, and it feels like longer. 

If Merrin were less tired, she would probably be WAY too self-conscious and worried about looking stupid to put a not-very-coherent note on the proposal saying that she has an Illegible Good Or At Least Better Than 35% feeling about it. But she's tired enough that social anxiety is only half online, so she feels incredibly self-conscious but posts her incoherent note anyway. 

"I'm going to sleep," she tells Halthis. 

Halthis is really jealous of Merrin's gut feelings! She obviously pulled up the discussion proposal as soon as she figured out what Merrin is staring at so intently, but unlike Merrin she can't afford more than fifteen seconds at a time of distraction, which means that looking up complex pathophysiology details is a lost cause. She has absolutely no idea why Merrin is flagging this as worth looking into! It sounds like a really doomy plan to her! (To be fair, Merrin agreed it was a doomy plan right now, which means that Halthis is not going to have to attempt it on her shift and spend the whole time panicking.) 

Merrin vanishes into her sleeping pod. Three hours to go before Kerrin takes over. 

Halthis is...feeling pretty out of her depth, actually! She's worked with patients this complex but she's never been the lead opper. Obviously she has all the support she could possibly need, but it's still pretty intimidating to be very clearly the least experienced person in the room, and still supposedly in charge! 

Well. If she can hand Kalorm over in three hours without having had another major setback in the intervening time, she'll feel okay about that. Time to focus. 

It's a very long and very tense and stressful three hours. 

At 11:35 pm Halthis manages to wean the epinephrine infusion down to zero. Finally. She is SO pleased with herself about this. Kalorm's heart rate seems to be pleased as well; he's hanging in there at 80 bpm, and his blood pressure is still hanging on in the vicinity of 80/50 (not great, but acceptable). His oxygenation isn't amazing - 88% or 89% - but, again, Treatment Planning considers that acceptable. 

They're checking (partial) lab panels every hour. Kalorm's lactate has stalled out at 50% higher than the top of the normal parameters and refuses to go any lower, but his inflammatory markers continue to inch downward. (Not very fast - at this rate it would take weeks to get all the way back to normal - but better than an increase.) His electrolytes are stable. His creatinine is increasing again but that's more indicative of the drugs affecting his kidneys than of underlying damage. His white blood cell counts at least aren't getting any worse. 

His hemoglobin is still just baaaarely below the normal reference range after the first blood transfusion. Treatment Planning is not delighted with this; in a patient with healthy bone marrow, they would let it slide even given his other risk factors, but Kalorm is separately at pretty high risk of developing worsening anemia over the next week before his bone marrow production is recovered. They'd like to give him another top up, not a full standard unit of blood but about 75% of one, over 90 minutes, pause if his lungs don't like it. 

...Kalorm's lungs do NOT like it. About 45 minutes in, his O2 saturation starts dropping. Halthis obviously pauses the blood transfusion immediately while she figures out if it's related, but even so, within 5 minutes she's up to 100% oxygen concentration on the ventilator and his O2 saturation is still at 81%. Treatment Planning does not think this is acceptable. They want to give him more bronchodilators - even though the good ones will inevitably stimulate his sympathetic nervous system and not be great for his heart - and they want to bump the ventilator pressures up a notch. 

The bronchodilators don't do much, but increasing the pressures roughly fixes the oxygenation problem! They eventually get back up to 87%, at which point Treatment Planning is willing to declare that fiiiiiine that is good enough for now.

His heart hates it, though! On the ultrasound imagery - which Treatment Planning fortunately requested they follow in real time - it immediately tanks his preload, the amount of blood managing to fill his atria and ventricles before the heartbeat. It's not helping that his heart rate is feeling the bronchodilators and is now up at 90. 

Treatment Planning really doesn't want to restart the epinephrine, but they're pretty maxed out on everything else, and Kalorm's rate of irritable ectopic beats over the last hour is negligible. They'll try easing down the anti-arrhythmics dose by 25%. 

This goes fine for a few minutes! Great, even! Kalorm's heart rate goes up some more, but stops at around 100, and his blood pressure is the best it's been all night, approaching 90/60.  

- at 12:19 am, he goes into rapid atrial fibrillation, with a very irregular heart rate averaging to around 160. 

He's actually not otherwise much more unstable! Atrial fibrillation is a less functional rhythm, he's losing the benefit of the atrial 'kick' that helps load up more blood into his ventricles to be sent onward, but Kalorm's left ventricle seems to be coping okay, and his blood pressure hangs on at 85/55.

(It's still pretty bad for him longer-run. His ventricles, confusedly trying to follow the chaotic electrical pattern higher up and taking random spikes in it as cues, are beating way too fast, so his heart is working harder, and meanwhile blood is pooling and hanging out being gently massaged by his pointlessly wriggling atria. If they let it do that for long he's definitely going to develop a blood clot, which they can't intervene to prevent because he's still slowly bleeding in his gut and it's not safe to give him any anticoagulation.) 

Treatment Planning thinks that the main provoking factor here was actually the bronchodilators. Which didn't help his lungs much anyway, so how about they don't try that again. They're going to hold off on re-increasing the anti-arrhythmic infusion, since his cardiac muscle contractility and thus stroke volume per beat seems to benefit a lot from the decrease. They'll try cardioverting him back to a normal rhythm with an electric shock. This is risky, because it might send him into a worse arrhythmia, but it's also risky to try to convert him back with drugs, because they might drop his blood pressure to an unsustainable degree - at which point his heart will quickly stop getting enough blood back to pump, and there's a downward-spiral-attractor to slip into pulseless electrical activity, which has a worse prognosis than a shockable pulseless rhythm. 

It takes seven minutes of clock time from the a-fib onset, and three shocks (each of which is a terrifying dice roll for everyone in the room) but they manage to get him back into normal sinus rhythm.

(The number of people in the room at this point is four. Halthis finds this pretty nerve-wracking, but Treatment Planning doesn't think this is an emergency worth waking Merrin for, and having any more people than that will inevitably make noise. As it is, they coordinate in complete silence via subvocalization microphones, while the other four backup medtechs hover next door.)

Kalorm's heart rate bounces around for a while but eventually re-stabilizes at 85. 

By 1:05 am his blood pressure is at 100/60, mean arterial pressure of 73. Treatment Planning doesn't incredibly trust this, but when he's still there at 1:15, they propose easing down on the angiotensin II. 

Kalorm's blood pressure...doesn't actually change much, even though by 1:40 am they're down to 50% of the previous max dose. He stays solidly between 95/55 and 100/60. 

It's unclear if the main positive factor here is a more functional left ventricle reducing the congestion in his pulmonary circulation, or a slightly lower total fluid intake per hour, or a slightly higher urine output per hour (his body is definitely responding to the decreased kidney-yelling and he pees over 60 ml during a 30 minute period), or just the higher ventilator pressures eventually being felt. But by 2 am, when Kerrin arrives to take over, Kalorm's O2 saturation is mostly back above 90%. He's also put out 90 ml of urine in the last hour. 

(Merrin sleeps through all of this. She didn't use the built in white noise machine, since that sure sounds annoying to the other staff, and she also didn't put in the provided earplugs because she doesn't actually want to sleep through a commotion. But she's really tired, and not that light a sleeper, and the sleeping capsule itself has soundproofed walls.) 

Kerrin is well rested and would be in a good mood if not for the fact that, you know, on her last shift they got Kalorm extubated and he was awake and communicating and physiologically stable, and then Merrin's bad feeling turned out to be MORE THAN JUSTIFIED and now he's in septic shock and on four different vasopressors plus an inotrope and barely maintaining his oxygenation thanks to all the pulmonary edema.

Also he apparently missed his midnight followup scan for the radioisotope-tagged white blood cell followup on his infection, because he was too terrifyingly unstable, and so she...is supposed to try to do that at some point? ALSO also, Merrin is asleep in a pod in the corner because APPARENTLY that is the only way they convinced Kalorm to consent to being reintubated period, and he still put it off long enough that he nearly died. 

In short! This is not completely surprising - she knew what Kalorm was up against here - but it's really not what she was hoping for! 

She is maaaaybe going to arrange to have stimulants on hand for tonight; she doesn't do that often, and she'll keep them in reserve for if things go very badly, but this sure seems like a shift where the odds of things going badly are...not low. 

She takes a handover report from Halthis. Entirely subvocalized, so that it won't wake Merrin.

(Someone has helpfully brought in sound-muffling booties for all the on-site staff so that they can walk around without making noise that will wake Merrin. USUALLY staff wear these to avoid waking PATIENTS and not random medtechs who have literally made a solemn vow not to leave the room until their critically ill septic patient is sufficiently recovered to wake up and tell them they can. Kerrin has pretty mixed feelings about this whole aspect of the plan, but admittedly one of those feelings is grudging respect for Merrin.) 

It's been a looooooong six hours and Halthis is tired, but not, like, tired to the point of being nonfunctional. She gives Kerrin a thorough report and then, with vast relief, heads home (or, well, to her relocated on-site apartment.)

Overall, Halthis feels - pretty good about having been tapped for this case and having agreed to travel to Default for it? She wouldn't have put herself forward as the best candidate to cover today's shift, if she had known what today's shift was going to look like; she knows that she's still relatively inexperienced, and she definitely doesn't have all the certs that could have ended up being necessary. But it's apparently important to Kalorm that he– she doesn't even completely have a handle on what he wants, here, it's so alien, but...he wants to be treated by people, who he's met, and - not by Civilization as an abstract concept, which he has a grudge* against? Or something?

And she is, in fact, a person who Kalorm has met, and she thinks she made some fraction of a social connection with him (not to mention persuading him to do a dialysis run, which she's still pretty proud of). Given that, she gets why they wanted her in charge, even if she had to lean really hard on her available support, and - she thinks she did all right? 

(She continues to be really jealous of Merrin's reflexes and intuitions, but, like, it's pretty clear that Merrin earned that the hard way, by doing a truly astonishing number of hours of sims. Halthis could get there in fewer hours - she's smarter - but it still sounds pretty hard.) 

Anyway. It was a learning experience for sure! Now that it's over, she can even find the space to feel pleased about that! And she did manage to hand over a patient in better shape than he was when she took over, despite all the excitement in the middle. 

She gets home and watches a TV-show-of-a-fanfic-of-a-popular-webcomic for a while, and then sleeps. 

* The Baseline construction that is translated here as "holds a grudge" has somewhat different connotations from the English phrase. Someone having a grudge can be expanded to "someone whose past training data caused them to internalize broad and very strong negative emotional updates about X, which are now sticky and hard-to-update, such that they now have strong expectations - which are endorsed, and roughly in line with explicit reasoning and beliefs- that any interaction with X will be awful, and are therefore very motivated to minimize ever having to interact with X, and/or to sabotage X as hard as possible".

The Baseline compound-word for this phenomenon doesn't imply that the internalized lesson was incorrect; it also doesn't especially imply that it was correct. Just that it happened as a predictable result of a human brain subjected to a certain set of experiences, and is now predictably going to be very very hard to shift. 

(There is a different Baseline term for a related kind of experience where the person in question doesn't endorse the lesson that their subconscious has learned, or finds it discordant with the explicit reasoning and beliefs; this could be roughly translated as "ugh field.") 

Kerrin will check all the Treatment Planning updates as she has a chance, and settle in for what promises to be an incredibly long six hours. 

Merrin continues to sleep. 

Kalorm continues to hang on. 

After the last blood transfusion top-up (and all the ensuing drama), his hemoglobin is now mid-normal-range. This actually seems to be doing him a lot of good, in terms of getting enough oxygen to his tissues; his lactate is finally dropping, and by 3 am falls below the upper cutoff for normal parameters. His blood pressure continues to be basically adequate, and Kerrin can wean down some of the vasopressors in cautious tiny increments. His cardiac function has definitely improved a little on the ultrasound followups; it's not great, even with inotrope support, but they have a little more wiggle room.

His heart rate is starting to creep up again, though in this case it's probably temperature-related; after many hours, his body is finally starting to spike a halfhearted low-grade fever, and at a temperature of 38.1 C his heart rate apparently wants to be around 105. It's not ideal, but his blood pressure is holding up - even increasing, Kerrin is able to get him entirely off the angiotensin II - so Treatment Planning wants to leave it for a bit, and not aggressively try to lower his temperature unless he goes above 39 C. Fever plays a not-fully-understood role in immune-system signaling, and overall Kalorm looks better at 38 C than he did at 36 C. As long as the inflammatory markers that hint at a dysfunctional cascade are continuing to drop - and they are - then letting him run a little warmer will hopefully help his body marshal its resources to fight the infection. 

They're still having trouble with his oxygenation, though. Halthis was never able to get either the oxygen concentration or ventilator pressure down, and despite getting very good breath volumes, Kalorm's O2 saturation is rarely above 92%. And that's with the head of the bed raised to 30 degrees. Lifting his head higher helps, and his blood pressure tolerates it, but his heart rate spikes to 120. Kerrin tentatively tries lowering his head to 15 degrees - which is the most that would be compatible with sticking him back in the scanner - and his O2 saturation instantly drops to 85%. So getting a followup scan is not really looking like a feasible plan yet. 

Getting a repeat scan is not one of the most urgent priorities right now; they have other tentative signs that Kalorm is improving. 

There continue to be a lot of things that Treatment Planning could try to improve his lung function, if not for the side effects on everything else! They really wish they could risk giving him a tiny dose of a diuretic; despite his modestly increased urine output he's still accumulating around 350 ml of net fluid intake every hour, just from the drug infusions, and at this point he looks pretty severely fluid-overloaded. Probably the only thing keeping most of that fluid excess out of his lungs, pushing it to hang out in his swollen extremities instead, is the pressure that the ventilator is holding. But his blood pressure isn't that good and his heart rate is already above 100. 

...They eventually agree on trying a small dose of one of the gentler diuretics, and instead of giving it as an IV push, they want it diluted and run over an hour. The hope is that it might be juuuust enough to cancel out the vasopressin yelling at his kidneys to retain water (without affecting the other vasoconstriction effects maintaining Kalorm's blood pressure) and his body can decide how much fluid it wants to get rid of. Obviously they want to stop it right away if his blood pressure starts dropping; they really don't want to restart the epinephrine. 

Based on repeat scans and some modest jumps in lung-specific cell injury markers, they're suspecting an inflammatory process is involved. It's not even necessarily related to the infection. Kalorm has been breathing 100% oxygen for multiple hours, and while this is currently necessary to get enough oxygen to his tissues - especially given that he's probably running a much higher metabolic rate than usual as his body fights the infection - it's also risking oxygen toxicity, with free radicals bumping around and damaging the delicate lung tissue. Prolonged exposure to high concentrations of oxygen can actually directly cause pulmonary edema, which means that even if his cardiac function keeps improving, at this point that won't necessary solve the respiratory issue.

Additionally, there's the problem where usually, when a patient is breathing room air, almost 80% of it is nitrogen, which hangs around keeping alveolae open; without any nitrogen to act as filler, alveolae at at risk of collapsing when they fully absorb the gas contents. Which means that right now they're relying on the higher ventilator pressures to prop open Kalorm's lungs and prevent this – and those pressures can also cause trauma and cell injury to the lung tissue. The risk is higher the longer he's on 100% oxygen, which makes it a priority to try improving his oxygenation in other ways so they can afford to decrease the concentration. Treatment Planning is not yet comfortable enough with his hemodynamic stability to consider positioning him prone, but Merrin's suggestion is starting to look more appealing.

For now, they want to chemically paralyze him. He's not noticeably fighting the ventilator in an active way, but even invisible muscle tension will still make it harder to push air into him, not to mention increasing his metabolic rate and oxygen needs. And then they want to switch to a different ventilator mode. Right now the setting is based on airway pressure, with a higher pressure to push in each breath and a lower baseline pressure; the actual volume per breath is a free variable, and Kalorm is spontaneously getting breath volumes of 700-800 ml, which is a good sign for his lung capacity but not necessarily actually good for his lungs right now. They want to try a volume-controlled setting instead; for that, the baseline post-exhalation pressure is set, but the ventilator just delivers a certain volume of air over a certain time interval, with the resulting airway pressure as a free variable. If they set a volume of 300 ml, and a rate of 50 breaths per minute, that should produce comparable per-minute ventilation even accounting for some of the volume being "dead space" that doesn't make it as far as his alveolae, and the current models think that it'll let them keep his lungs open and ventilated with lower total pressures. They're also looking at fiddling with the ratio of inhalation-time and exhalation-time.

(One of the downsides is that this sort of mode is incredibly uncomfortable for even slightly awake patients. However, Kalorm is currently deeply sedated and is not going to notice.) 

This might not work! It might turn out to be worse than the current setting, either for his oxygenation or his cardiac output. They're proposing a gradual transition over five minutes, rather than an immediate shift - first switching to volume-controlled with the current set respiratory rate of 16 and volumes of 700, check that this is in fact producing a comparable or lower peak airway pressure, and then gradually shifting the volume and rate in synchrony, so that they can easily reverse it if his response isn't what they're hoping for. 

Kerrin is kind of stressed about this but she will very carefully execute on those instructions! 

Giving Kalorm a slowly infused tiny-baby-dose of diuretics doesn't drop his blood pressure! It also doesn't increase his urine output by that much, probably because there are multiple signaling cascades, including ones his body is producing on its own rather than in response to drugs, telling his kidneys that this is an emergency situation and they should be conserving water. But it looks like it'll get him from 150 ml/hour output to more like 250 ml/hour, which means he'll at least be less net-positive on fluid intake. 

Chemically paralyzing him actually has a noticeable effect right away, even before they start mucking around with ventilator pressures. His heart rate settles down to 95 - so there probably was some invisible muscle tension that was burning energy - and his oxygen saturation slowly climbs to 96%. 

The ventilator-setting transition is a bit rougher. It's working about as well as expected with his lungs, but it seems to be seriously confusing his blood pressure about what's happening to it. There are some spikes, and some scary drops, and Kerrin doesn't have a lot of levers with wiggle room on them to smooth this out. They end up having to make the change very slowly, over fifteen minutes, giving Kalorm's body some time at incremental stages to get used to the faster rate. 

But by 4 am they have him fully on the new ventilator-setting configuration, moving enough air - and, yes, with lower peak airway pressures - to maintain an O2 saturation of 99%. Which is higher than they need it to be, so Kerrin can alternate dropping the O2 concentration and the baseline post-exhalation pressure, targeting a range of 90-92%.

The lowest Kalorm will tolerate is 90% oxygen, but at least right now, he actually lets her go down substantially on the ventilator pressure. They're going to have to keep monitoring his scans closely – it's possible that the lower lobes of his lungs will start gradually collapsing or filling with fluid, at this pressure – but in the meantime they're causing less damage. 

Kerrin is going to watch him so closely. She has an itchy feeling about not having up to date scan imagery, though Treatment Planning is right that it probably won't give them decision-relevant information that they don't already have.

She is also definitely keeping an eye out for things that are going unexpectedly well, because her emotions could really use some good news tonight. 

Things which are going well: Kalorm's gut is clearing out its contents pretty effectively! On ultrasound imagery, the distended bowel loops are significantly decompressed, though there are still pockets of gas that haven't yet been broken up by the anti-foaming agent to make their way onward. The liquid stool draining from his rectal tube is now testing positive for trace metabolites of antibiotic! It's still a pretty disgusting color - the eventual goal is to get it to mostly clear - and also tests positive for occult blood, but it's much more liquid, no longer very sludgy. He's consistently dumping out around 300 ml/hour of it, more than the 200 ml/hour going in via the nasoduodenal tube. 

The drainage from his nasogastric tube still on suction is now mostly clear, which is what pure gastric secretions should look like, and analysis doesn't show more than tiny trace quantities of bile. 

That is good news! Kerrin is appropriately pleased about it! 

...She's less pleased about Kalorm's next lung scan. 

He's still maintaining an O2 saturation of 90%, just barely, and his lung-injury markers have stopped rising - a hopeful sign that the lower peak airway pressures are helping mitigate the ventilator-associated lung damage - but it does look like this mode is also less effective at keeping his lungs open. There are growing regions of consolidation, indicating collapsed lung regions - the lower lobes of both lungs are no longer especially moving air, and there's also quite a lot of semi-collapsed lung tissue in the backs of his lungs, currently under more pressure just from gravity - especially the middle region of his left lung, lying under the weight of his heart. 

His still-distended abdomen probably isn't helping. (They've cleared out the most scarily distended and unmoving areas of his small bowel, but there's still a lot of total bowel contents, the intestinal wall tissue itself is pervasively swollen with inflammation, and with the fluid overload combined with leaky capillaries, he's also starting to accumulate random generalized tissue edema.) With his diaphragm chemically paralyzed along with everything else, there's no muscle tension to push back against the weight of his abdominal organs compressing it, and squashing the lower lobes of his lungs.

On the bright side, his blood pressure continues to hold up just fine, and Treatment Planning approved continuing the slow baby-dose rate of the diuretic. He's frequently been as high as 105/60, and Kerrin is working on cautiously decreasing the vasopressors, leaving the methylene blue at the max rate - it seems to be helping with the cardiac dysfunction - and not touching the inotrope, but alternating between incrementing down on the first-line catecholamine blend and the vasopressin. With his temperature down to 37.8 after they chemically paralyzed him, his heart rate is hanging steady at 90, and his urine output is on track to hit 400 ml in the next hour (if it keeps it up for the whole hour), almost enough to get him to neutral on fluid balance. 

...Treatment Planning is going to promote the prone-positioning suggestion to top level consideration. At this point, it's sort of the obvious thing to try for 'regions of a patient's lungs are collapsing for gravity reasons at a ventilator pressure that would be otherwise fine.' It's still definitely risky, but Kalorm's hemodynamics are doing better, and they have quite a lot of wiggle room on various drugs; if his heart doesn't like it, they'll be able to go up on vasopressors to get him through transitioning back to supine. And Merrin had a feeling that his heart would benefit from it. Merrin's feelings aren't infallible but they're worth taking seriously. 

They kind of want Merrin to look at him first, but it's only 4:30 am, definitely too early to wake her. (And getting the number of people in here that they need on-hand to actually prepare the cocoon mode and flip Kalorm would almost certainly wake her anyway.)

They'll let the expert prediction markets chew on it for a while and put together an actual protocol, and hopefully Kalorm will manage not to deteriorate any further before Merrin is awake. They'll tolerate an O2 saturation as low as 88%, and brief drops below that, but if he drops and stays low then they'll increase the ventilator pressure again as an interim measure. 

Kalorm's O2 saturation is definitely trending downward. Not fast, but by 5:00 am he's just baaaaarely hovering at 88%. His 5:00 am blood gas shows a partial pressure of oxygen just below the normal lower-end cutoff. With less lung tissue being accessed for gas exchange, his CO2 is also starting to rise – and the ventilator is having a harder time meeting its goal volume of 300 ml. 

His other lab checks come back decent! Lactate is now mid-normal range. Electrolytes are fine; his creatinine has gone down a little again now that his kidneys are  putting out more urine. (It's looking pretty likely that he won't need any more runs of dialysis, unless the sepsis causes an additional kidney injury, which the market thinks is only 30% likely at this point.) Hemoglobin is stable. His immature white blood cell counts have gone up a little more, but his mature neutrophils count is also a teeny, tiny bit higher. 

They'll try going up a small increment on the post-exhalation baseline pressure - and they want to drop the goal breath volume to 275 ml but increase the rate to 60.