Andrew Miller: Post-Bondi massacre blood donations bring home just why it’s vital we contribute

I have one daughter sampling dango in chilly Japan, the other is snorkelling with her mum down where the hot limestone bluffs cool off in the green-blue ocean, and my ever-temperate son is blurring the lines somewhere between work and play, as all the best people do. Many parents believe that our only important checklist, our primary motivation and weakness, is the wellbeing of our family. We balance engagement with other good causes, but no mother or father can sleep soundly when they are concerned about a late or absent seat at the family dinner. I ponder over my kids a few times every day. They are my Roman Empire, and I would probably die for them. Probably, because obvious conditions apply regarding the gravity of their situation and the efficacy of the sacrifice. I would not offer my life for an iPad or streaming service subscription, but say there was a hypothetical emergency where my entire blood volume was required, then I would urgently offer every last drop. Before the propagation of investigative journalism and critical thought, many people felt the same way about king and country. While I am not interested in dying in the name of Albo or King Charles III during an invasion of Venezuela or Greenland, what proportion of my blood would I give for my community? If ever you doubt the philanthropy of middle Australia, remember that in response to two vile terrorists in Bondi over 100,000 people booked appointments to donate blood. Operating theatres are already cool enough at 21 degrees and 55 per cent relative humidity, but a serious chill runs through them whenever massive haemorrhage, sometimes bleakly known as “audible bleeding” becomes evident. Humans do not carry a whole lot of spare blood. The denominator is 80mL/kg, or 5.6 litres of whole blood for a 70kg person. Once you lose twenty percent — about a litre — we start to get twitchy, depending on whether it’s likely to continue. There is a spiral that patients get into, when their ability to coagulate deteriorates because of the complications of blood loss itself. Doctors do what we must to stem further losses, while we invoke a pre-ordained team algorithm that includes testing coagulation parameters; coordinating the immediate provision of multiple blood products; giving pro-coagulant drugs like tranexamic acid and calcium, and keeping the patient warm and well ventilated. The average blood donation at Australian Red Cross Lifeblood is 470mL, or 8 per cent of an adult’s supply. A large transfusion — more than your entire blood volume within 24 hours — is regularly required in our hospitals for obstetric haemorrhages, trauma cases or gastrointestinal bleeds. That is more than 10 units of packed cells from 10 donors who cared enough to act. When a lot of blood is disappearing up the surgeon’s sucker, we might perform intraoperative cell salvage with a machine that filters the patient’s own blood for reinfusion. I always reflect during such cases that it is great to practise medicine at a time when science and technology rules over superstition, magical thinking and uneducated influencers. Long may it continue. We ate as much food as possible, beginning with family dinner on Christmas eve, anchored by prawns and a turkey breast roll — 70 degrees — served with crispy potatoes, roasted parsnip, pumpkin, onion, fennel and broccolini. There was an ugly salad that I clunked together with absolutely no finesse. Luckily, we live in a part of the world where beautiful fresh produce is the norm, and my incompetence went unnoticed. The clock ran too fast on our evening, which is always a good sign, and soon the magical second stomach that is reserved for warm desserts was called into action. We cannot guarantee the safety of our kids, as they run off to experience all that the world has to offer, but we can absolutely donate a little blood. You never know, it might just help someone’s child make it home for their family dinner.