Therapeutic Window

by Steve Low

Thirty-six hours had passed since Gibbs had poked his nose into the tearoom. Rostered onto the nightshift, I watched with growing dismay as Mr Hart’s condition took a further deterioration. Melanie was calling to my little doctor’s bedroom at eleven o’clock. The patient’s deteriorating lungs were putting that rendezvous in jeopardy.

  Boatwood on his evening ward round, looked at the data pensively. “There’s no room to move here,” he muttered. “He’s been on eighty percent oxygen for two hours now. His arterial oxygen is still falling. His lungs are filling up with water. He’s got ARDS. We’ll have to put his PEEP higher.”

  “Why not increase the inspired oxygen?” Mary the nurse asked. Her lips seemed black, against a chalky white face.

  “Well we could,” Boatwood said. “But it’s not a long term option. Oxygen at these high concentrations will cause fibrosis in his lungs. If it is used for several days, you will get permanent damage. So no, I’d go for increasing the PEEP. His circulation is reasonably stable. It can handle some increased intra-thoracic pressure.”

  I moved to the ventilator, reaching out for the control knob. “Up to twenty-five?” I asked.

  “No . . . No make it seventy,”

  I laughed. “Seventy?” I glanced back at the Professor. But there was not a trace of amusement behind the horn-rimmed spectacles.

  “Seventy,” Boatwood repeated. “This man will die, unless we do something drastic.”

  “Yes, but seventy, that’s unheard of,” Mary butted in. Her little mouth was pinched at the corners, her nostrils flattened and blanched.

  “I repeat, the patient is going to die.” Boatwood said, emphasising each word. “Conventional treatment is failing. Let’s show a bit of guts and take control.”

  Impressed by Boatwood’s resolve, but sensing that the proposed treatment perhaps wasn’t properly validated, I twisted the knob around to seventy. I watched the baseline airway pressure gauge indicator rise to seventy. We all knew where to look next. I imagined the lungs growing and growing – surrounding the heart with drum tight tentacles. And venous blood, trying to return to the chest, would be meeting a 70mmHg wall. There was bound to be a fall in cardiac output. Sure enough, as we watched, the blood pressure began to descend.

  When it got to eighty, Boatwood cleared his throat. “That’s no good. Start an adrenaline infusion. The pigs withstood hyperPEEP in the end. And so will Mr Hart, with a little help from our friend adrenaline. This heart needs supporting.”

  Mary began filling a large syringe with the adrenaline solution. She and I exchanged glances. Mary shook her head and grimaced. When it was ready, Mary plugged the end of the adrenaline infusion line into a port of the central venous line and I began immediately to wind up the infusion rate. When the rate was up to twelve mls per hour, we had what we wanted. The blood pressure was 105mmHg and the hyperPEEP had made the arterial oxygen saturation improve markedly.

  “Fine,” said Boatwood, his eyes softening under the fluorescent glare. “Now I’ll just confirm that we’re winning, with a blood gas analysis. Then we can all go to bed – well, I can go to bed anyway.”

  Porcelain Mary, perhaps impressed by the figures, sprung into action and provided the professor with a blood sample from the arterial line. He virtually snatched it from her grasp and strode smartly through a store room, to a mini-laboratory across the back corridor. Within minutes, he was back clutching the print-out. “You can turn down the oxygen,” he said, his eyes ablaze. “The oxygen saturation is ninety-six.”

  I surveyed the slip of paper. I imagined the heart squeezed by its lung envelope, struggling manfully to force enough blood out to the waiting organs, the liver, the kidneys . . . the brain – and the adrenaline soaking into the screaming myocardium, driving the heart muscle harder and faster.

  Over the course of the evening the patient remained stable, so that when eleven o’clock came around, and Melanie slipped into my bedroom, I was there waiting for her.

  “Green’s in his office,” she murmured, her complexion reddened by the night air.

  “But he’s not on call tonight,” I said, pulling her in close. Green was always in the hospital. We both knew that. He was addicted to being the dedicated doctor – it was a calling that over-rode everything else in his life. “There’s a problem case tonight unfortunately. I’m liable to be called at anytime.” I said. As if on cue the telephone shrilled. A three second sustained burst. I swore. I scooped up the receiver. Mary needed me to assess Mr Hart.

  “Is there a problem?” Melanie asked.

  “Porcelain is up in arms about something. Hopefully I won’t be long.”

  “I’ll wait for you for a while,” she said. “I’ll just rest here on the bed.”

  Outside in the dark corridor, the air conditioning hit me with an blast. I shivered momentarily before entering the barn through the double swing doors. Porcelain Mary had beds three and four. They were both ventilated patients. There was Mr Hart on the hyperPEEP, and a patient in bed three called Miller.

  “Mr Miller has developed this fast heart rate,” Mary said, pointing at the monitor screen. The heart was beating at 130 beats per minute. I was familiar with the man. He had been admitted to the ICU earlier in the day, after failing to breathe adequately following gall bladder surgery. He had emphysema as an underlying condition.

  “Is he breathing much for himself?”

  “He’s not synchronising well with the ventilator. I’ve had to use quite a bit of diazepam.”

  “We don’t want to overdo the sedation, or we’ll never get him going in the morning.”

  Mary looked at me, her thin black lips a straight line. “Boatwood said to keep him quiet – even paralyse him if necessary.”

  That was the trouble with being a trainee, I mused. There was always someone above you with greater authority. “Well if you do paralyse him, make sure he gets adequate sedation as well.”

  “I’m not an idiot,” Mary said, eyes blazing. “What are you going to do about this heart rate?”

  “He’s out of sync with the ventilator. He’s probably retaining CO2. They’ve either got to be awake enough to receive commands, or alternatively you wipe them out with enough sedation to let the ventilator take over. We’re in no man’s land with him. I can’t reverse the sedation, so we will have to take him deeper.”

  I felt quite pleased with myself, after the exchange. I crossed to bed four, to check on Mr Hart. I looked in awe at the drum tight, dilated chest. The ventilator breaths, were barely causing any noticeable movement of the chest wall. I aspirated a blood gas sample from the arterial line and took it out of the barn to the mini-lab. The oxygen saturation was still satisfactory. On the way back, I noticed the light on in Green’s office. I walked silently down the corridor, towards the light. The door was partly open and I stopped outside to listen. I could hear Green’s breathing and his fingers tapping on a computer keyboard. If Green knew I had one of the nurses in the bedroom!

  Back in the Barn, I stapled the blood-gas printout to Hart’s notes, then headed for the exit. Passing by the patients in beds one and two, I noticed the male nurse looking after them, slumped in a chair, almost asleep. I went over to him. It was Tucker. It was well known that Tucker managed a geriatric home during the day and often did an ICU nightshift as well on the same day.

  “Bit tired Tucker?” I ventured.

  “Stuffed,” he said sitting upright.

  “Today’s cardiac patients seem O.K,” I said.

  “Not a problem fortunately..”

  Melanie was asleep on the bed when I returned. I lay down beside her, wrapping my limbs all around her. “You’re very cold,” she murmured, from the depths. “How is that patient with all the PEEP?” She opened her eyes.

  “Yeah, he’s going well actually.”

  “I don’t see how Boatwood can just do that.”

  “Do what?”

  “Put on all that PEEP – without some authority condoning it.”

  “Well in reality, a c
linician can decide for himself, when he thinks that research has shown the safety of a technique. Drugs are more closely governed maybe. But something like a respiratory therapy? It’s anything goes really.

  “But there were problems with the first pig study,” Melanie said yawning.

  “Boatwood prefers to think that a mechanical problem occurred. A power cut or surge. Something like that.”

  “It seems weird to me that he can just disregard the problems that occurred with the first experiment. If you add the two studies together, there were three deaths from 12 pigs. You wouldn’t think that would justify immediately using the therapy on humans.”

  “True. Boatwood’s ruled out the first study. He’s assumed some technical problem occurred while we were out of the lab.”

  “What’s he really like; Boatwood? Green’s always grumbling about him.”

  “Oh he’s quite likeable. Bit of the absent minded professor about him. He does tend to take a polarised position on things. That’s what irritates some of the others I think.”

  “Green is always finding fault with others,” Melanie said.

  I laughed “He’s always right too. I can’t remember an instance when he was wrong.”

  We lay back together. Melanie pulled the top cover up over us both and we clung together for warmth. It was after midnight and we both fell a sleep.

  The phone shattered the peace at half past two. Porcelain Mary’s strident voice shot down the line. “Mr Hart is going off.”

  I sat up on the edge of the bed. “Ah Christ,” I lamented.

  “God, it’s late. I fell asleep. I’d better run,” Melanie whispered.

  I crashed irritably through the double doors, making a bee line to the problem patient.

  “His blood pressure is dropping,” Mary said.

  I looked at the monitor. The pressure read 84. As he watched it slipped to 83, then 82. “When did it start falling?” I asked.

  “It was a hundred ten minutes ago.”

  I looked over at Tucker, to see if he had noticed anything. One look and I realised Tucker was in no state to observe anything. “You’d better give him a kick,” I said to Mary. I turned Hart’s adrenaline infusion up a couple of notches, to buy time for a rapid physical examination. I was worried about a burst lung – the killer of the pigs. However the airway pressure was unchanged and both lung fields were fully aerating. I palpated the radial pulses, gauging their volume and pulse pressure. I felt the temperature of the skin of the extremities and tested for capillary refill in the nail beds. Capillary refill was poor and the pulse pressure weak. I looked at the central venous pressure trend. It was stable. With this information I phoned Boatwood. “The blood pressure drop is associated with vasoconstriction so he’s either under filled or has poor cardiac output due to poor cardiac function,” I explained to the professor.

  “What about the ECG – any sign of ischaemia?” Boatwood croaked down the line.

  “No ST or T wave changes.”

  “Mmm – doesn’t rule it out though. I’d try more fluid volume – say a 250 ml challenge. Be cautious with the adrenaline but you may have to take that higher by the sound of it.”

  “You don’t want to take off some of the hyperPEEP?” I asked

  Boatwood’s voice rose up a couple of notches. “There’s no indication that it’s a hyperPEEP problem. It sounds more like hypovolemia. What about sepsis – have you done a sepsis work up?”

  “No. I’s thinking more about MI.” I said. “Early sepsis would be more likely associated with vasodilation and a hyperdynamic circulation.

  “Ah well that can be a trap making an assumption like that. It could be a rapidly progressive infection with poor myocardial function and vasoconstriction. You’d better get on to a sepsis work up just in case,” Boatwood said and rang off.

  I was about to add that the temperature was plum normal but then of course Boatwood would have invoked the idiosyncratic cases where the temperature is normal or even reduced during sepsis. I duly opened the tap on the intravenous line and let the fluid run into the central veins. My palms turned to sweat though, as I watched the blood pressure continue to trend downwards further. “Oh shite,” I said to no one in particular. “I’d love to try taking that hyperPEEP off.” Instead I wound the adrenaline infusion higher.

  Tucker appeared at my shoulder. “Green is around. I heard him talking to Tony. Shall I get him to help?”

  “You must have been dreaming. You’ve been unconscious.”

  “He’s gone home,” Porcelain said. “He was here before, and Drummond, but they left to go home. About ten minutes ago.”

  The blood pressure hit 65. A continuous alarm sounded and the digital readout began to flash.

  “Get a pressure bag,” I barked, looking with alarm at the ECG trace which was starting to slow and show multiple ectopic beats. Mary wrapped the pressure bag around the saline, pumping it up and driving the fluid into Hart’s blood stream. But the blood pressure continued its descent, down through 60. “Get Boatwood in,” I shouted. “We’re in the crap here.”

  “What about the hyperPEEP?” Porcelain Mary asked, her face drained of all colour. I wanted to take it off. The subconscious hand-break of the will of Boatwood was all that had prevented me taking it off earlier.

  “Take it off . . . Take it off,” I exhorted. “And adrenaline up to 25 micrograms per

  minute. Let’s keep squeezing the fluid in.”

  “BP is 55,” Tucker called. “Now 56 . . . 57 . . .still 57 . . .59, 65! We’re getting somewhere now.”

  Green appeared at the double doors, immediately spotting the fracas. “What’s going on here?” he asked, an edge entering his voice. And behind him, there was Boatwood, out of breath, his own urgency obvious to all. I explained the current situation, being careful to attribute the improvement had occurred to the giving of IV fluid, increasing the adrenaline rate as well as removal of PEEP. I was trying to avoid embarrassing Boatwood.

  “BP 88,” Tucker called again.

  “You’ve done well Gerry,” Green said. “But how did he get into trouble in the first place?”

  Boatwood interjected. “He’s post nephrectomy – major intraoperative haemorrhage, and subsequent ARDS. He’s needed maximal therapy to prevent overwhelming hypoxia.” He neglected to add that he had been applying 70mmHg of HyperPEEP over night.

  Green only appeared to be half listening. He was looking intently at the ECG trace up behind the patient’s head. “There’s your problem Prof,” he said. “Look, those ST segments are getting more and more elevated – even as we stand here talking. I’ll bet my bottom dollar he’s having a myocardial infarction. He’s probably been ischaemic for a while – that’s why your cardiac output and blood pressure have been falling.”

  Boatwood was only too willing to agree – no doubt eager to focus on something other than the fact that hyperPEEP had been in use. We started a glyceryl-trinitrate infusion, and optimized blood pressure with a metaraminol infusion and more volume. Green, apparently satisfied with the events, headed out of the unit. Boatwood stood staring at the patient for a few seconds.

  “Tidy him up can you,” Boatwood said to Mary. He walked away, over to the central station. I followed him. He watched as Boatwood worked at the computer, flicking through the electronic trends. The professor activated a printout for each trend.

  “It was all quite stable for hours, then . . . He went off quite quickly.” He murmured.

  “A heart attack at that stage seems plausible?” I ventured.

  “Mmm maybe.. If so the knives will probably be out. They’ll say the heart was made ischaemic because of the large amounts of adrenaline required to counteract the HyperPEEP effect on the circulation. Something like a preceding pulmonary embolus inducing increased work on the heart would be a better scenario.”

  “Better?” I began to speak then faltered. There was no reason to carry on with my enquiry. Boatwood clearly wanted a cause for a heart attack, other than
that of a heart struggling in the grip of hyperPEEP.

  “We’ll get a V/Q scan in the morning, With any luck it might confirm a pulmonary embolus,” Boatwood continued.” And there’s always sepsis. You did do a sepsis screen earlier?”

  I nodded in assent.

  Boatwood shook his head as if in disbelief. He inhaled deeply. “The knives will be out,” he said, standing up, “unless there is sepsis or a PE.”

  I left him there and went to check on a few of the sicker patients, before going to my room. Mr Miller, next to Mr Hart, was sweating profusely. His heart rate was back up at 130.

  “Hey Mary, is this man paralysed?”

  “Yes,” she said, not looking up. She was washing Mr Hart down.

  “Well he’s sweating. You’ve got to sedate him. He could be awake in there.”

  “I’ve been busy – didn’t you notice?” she snapped “There’s diazepam under the chart table.”

  I injected ten milligrams of the drug slowly. “Poor bastard,” I said. “Let’s hope he hasn’t been conscious through all this.”

  In the bedroom, Melanie’s fragrance had impregnated the pillow. I inhaled, deep down into my lungs. I ached for her physical presence. But my body was wracked with tiredness and sleep came swiftly.

  The next day I slept soundly and was back in the Barn at 6pm to commence another night shift. Boy Wonder was in a ferment, his face alive with enquiry, “Wow. You’re right in the thick off it,” he announced as I entered the tea room.

  “Oh yeah,” I said, pretending to be in the dark.

  “Oh come on,” Boy Wonder smirked. “Haven’t you heard? Nobody is talking about anything else. Mr Hart died earlier this afternoon. Looked like an overwhelming heart attack.”

  If it was true, Boatwood was indeed in the gun. I could guess at the route the rumour had taken. Starting from the righteous Porcelain Mary, word would have reached Green and Gibbs in quick time and the moral outrage would now be manifest . . .

  Chapter 8