Chapter 29
Intraoperative Hemorrhage

Resuscitating a patient with acute bleeding is one of the core skills that the hospital depends on anesthesiologists for. This section focuses on the management of rapid, uncontrolled hemorrhage: a scenario that, while theoretically straightforward (“give blood fast”), is often complicated in practice. Common pitfalls include delayed recognition, disorganized team dynamics, and logistical barriers such as inadequate IV access or delayed blood product delivery. These are high-stakes moments where preparation and execution matter deeply.

This is a skill set that requires deliberate maintenance. If your practice doesn’t routinely involve high-blood-loss cases, it can fade quickly. But regardless of your subspecialty, you will eventually face a massive hemorrhage, and your patient’s life may depend on your ability to respond decisively and effectively.

These are high-pressure situations. The more you can see and reflect on early in your training, the more comfortable and capable you’ll become.

Adequate IV Access

When bleeding is anticipated, preoperative planning is essential. Discuss the case with your attending, anticipate the spectrum of blood loss possibilities, and establish a plan for blood product availability and delivery. Bleeding risk is not always intuitive. Read about the surgery beforehand, especially in cases you’re less familiar with.

“Large-bore access” doesn’t just mean having two IVs. It means having more than two IVs, 18 gauges or larger, that are reliable, well-secured, and visible during the case. The quality, location, and performance of the IV matter more than the sheer number of lines.

Refer to Table 29.1 for a comparison of different IV types and approximate flow rates. You will, over time, develop a “feel” for how useful each type of IV line is in an emergency. As an anesthesiologist, you always want to overestimate IV access and never underestimate it. The difference can be life and death.

Table 29.1 Approximate time to infusion of 1 mL fluid sorted by IV size. RIC = rapid infusion catheter. Notably absent is the “triple lumen” CVC where flow rates are considerably slower than even the four-lumen CVC. A triple-lumen catheter is not a large-bore resuscitation line. PICC lines and implantable ports are even more flow-limited, such that they cannot accommodate rapid infusion of any type. A key takeaway: well-functioning peripheral IVs generally offer superior flow rates compared to non-sheath central lines.

Size	Type	1,000 mL infusion time (with pressure bag)
8.5 Fr	RIC line	46 seconds
7 Fr	RIC line	1:00 min
8.5 Fr	Sheath introducer	1:05 min
14 Ga	Standard IV cannula	1:30 min
6 Fr	Sheath introducer	2:10 min
14 Ga	Angiocath (13.3 cm) IV	2:10 min
16 Ga	Standard IV cannula	2:20 min
18 Ga	Standard IV cannula	4:23 min
14 Ga	4-lumen CVC	5:20 min
20 Ga	Standard IV cannula	6:47 min

Note that flow estimates in Table 29.1 are idealized and don’t account for real-world variables like catheter kinking or poor vein quality. Excess IV tubing can also increase resistance.

Preparing for Transfusion

As the anesthesia provider, you are solely responsible for ensuring blood can reach the operating room quickly in the event of hemorrhage, regardless of how “routine” the case may seem. There is nothing more terrifying than watching a patient exsanguinate while waiting for blood to arrive. Preparation is not optional.

My first goal is to demystify blood bank terminology. Your perioperative colleagues will often use terms interchangeably, which can lead to dangerous misunderstandings: “I thought you said blood was available!”

Type and Screen: This is the first step. It determines the patient’s ABO/Rh blood type and screens for non-ABO antibodies. It should be done within 72 hours of surgery to remain valid, although centers may vary in the duration of validity. For inpatients, a reminder to the team may be necessary. Maintaining an active type and screen is often neglected by inpatient teams. If the patient is “antibody positive,” this means they have alternative, non-ABO, non-Rh antibodies. This will make crossmatching blood more complex. This is critical information from the type and screen because it signifies that blood may take many hours to prepare, potentially requiring the case to be delayed. This is why type and screens are ideally obtained 12–24 hours before surgery. It allows for advanced planning in the event of a positive antibody screen.
Active Type and Screen: This means there is a valid type and screen on file. If no antibodies are present, an active type and screen is usually a reassuring sign that crossmatched blood can be ready in 10–15 minutes.
Type and Cross (Crossmatch): This is the next step in the blood procurement process. This is an order you dispatch to the blood bank requesting a specific number of units. The blood bank will now select and hold units for you, matched against the patient’s type and screen. They usually do this electronically, but for patients with complex antibodies, they may test an aliquot of donor and recipient blood together in the lab. This process takes around 30 minutes for usual ABO crossmatches, but can take 2–4 hours if non-ABO or non-RH antibodies were detected on the type and screen. Now the blood is ready for immediate pickup. This is usually what providers mean when they say “blood is ready,” but always verify. Someone may say “we ordered blood” or “we set up units” when they really only mean that a type and screen was ordered.

In cases where you expect to give blood (“we want blood in the room!”), ensure that you have crossmatched units and not just an active type and screen. Crossmatched units may remain in the blood bank, be moved to OR-area refrigerators, or be kept in a cooler in the room. This should be discussed ahead of time. Platelets should not be kept in a cooler.

No Type and Screen? What Now?

In emergent or unanticipated bleeding scenarios, the blood bank can provide uncrossmatched blood: typically, O-negative blood or blood that can be quickly electronically crossmatched based on the most recent (even expired) type and screen. This is suboptimal, but necessary if bleeding is life-threatening. Once a current type and screen is obtained, transition to crossmatched blood will occur.

Massive Transfusion Protocol (MTP)

Most centers have MTP programs, which can be activated in the setting of ongoing, uncontrolled bleeding. This usually includes a cooler with pre-set ratios of PRBCs and FFP (e.g., five RBC, five FFP). These may be a mix of uncrossmatched and crossmatched products.

Administering Blood Products

Use blood tubing with filters to prevent microclot and debris infusion.
Do not use filters when administering platelets.
Fluid warmers should be used to prevent hypothermic coagulopathy, but be mindful: some warmers have excessive tubing, which can decrease flow rates, especially with viscous products.
Pressure bags and gravity-squeezing chambers are essential tools to expedite transfusion.
Monitor for extravasation, particularly with high-pressure infusions through peripheral lines.

Emoji of a lightning bolt. Takehome: Understanding your hospital’s blood bank terminology and the EMR sequences necessary to procure blood is your responsibility, and yours alone. As the arbiter of perfusion and resuscitation, you are ultimately responsible for blood availability. If a case is set, proceed with blood not yet available; this should be communicated with the procedural team, who share your goal of having properly available units to proceed safely.