Sepsis Explained: Hour-1 Bundle, qSOFA, Lactate & Septic Shock

Fever and new confusion: sepsis? 0:00

0:00 Bed six. Your patient has a fever, a cough, and new confusion that wasn’t there this morning. Heart rate, 118. Breathing, 26 a minute.

0:11 Blood pressure, 88 over 50. Is this just an infection, or is it sepsis? And what do you do in the first hour? Let’s take sepsis from the inside out: what it is, how to spot it, the first-hour bundle, and the exam traps.

What sepsis is (Sepsis-3, septic shock) 0:29

0:31 Start with the definition. Sepsis is life-threatening organ dysfunction caused by a dysregulated host response to infection. In plain words: the infection is the trigger, but the body’s own response is what injures the organs. At the bedside, organ dysfunction means an acute rise of 2 or more points on the SOFA score.

0:54 Septic shock is the sickest subset. The patient needs a vasopressor to keep the MAP at 65 or higher, and the lactate is still above 2, despite adequate fluids. In the Sepsis-3 data, hospital mortality in septic shock was over 40 percent.

What happens inside the body 1:12

1:15 So what goes wrong inside? Germs, usually bacteria, trip the immune alarm, and immune cells flood the blood with signals called cytokines. Those signals widen the blood vessels, so resistance falls and blood pressure drops. The vessel lining turns leaky, so plasma slips out into the tissues, and the circulation runs low.

1:39 Clotting switches on too. Tiny clots plug small vessels, anywhere from a falling platelet count, to DIC. And injured mitochondria make less energy, so cells struggle even where oxygen arrives. The result is organ dysfunction: confusion, acute kidney injury, lung injury up to ARDS, and a rising bilirubin. Later, the response can swing the other way, into a long stretch of immune suppression.

Who is at risk and common sources 2:10

2:12 Who is at risk? Any infection can lead to sepsis, but the CDC names groups at higher risk. Adults 65 and older, babies under one, and people with chronic conditions like diabetes, lung disease, cancer, or kidney disease. Also weakened immune systems, a recent severe illness, surgery or hospital stay, pregnancy or the postpartum period, and sepsis survivors.

2:42 The infections that most often lead to sepsis start in the lungs, the urinary tract, the skin, and the gut. Each year about 1.7 million U.S. adults develop sepsis, and at least 350,000 of them die in the hospital, or go to hospice.

Recognizing sepsis: SIRS, qSOFA, NEWS, lactate 3:00

3:02 Now, how do you spot it? The older SIRS criteria look at temperature, heart rate, breathing rate, and white blood cell count. But SIRS measures inflammation, and inflammation alone isn’t sepsis. Sepsis-3 added qSOFA: a breathing rate of 22 or more, altered mentation, and a systolic pressure of 100 or less.

3:27 qSOFA flags patients with suspected infection who are likely to do poorly, but it was never meant to define sepsis. So surviving sepsis, 2021, recommends against qSOFA as a single screening tool, compared with SIRS, NEWS, or MEWS. That’s a strong recommendation. The 2026 update keeps it strong: NEWS, NEWS2, MEWS, or SIRS, over qSOFA.

3:56 NEWS scores seven bedside items: breathing rate, oxygen saturation, oxygen use, temperature, heart rate, systolic pressure, and consciousness. SOFA is the fuller score: six organ systems, from breathing and clotting, to the liver, circulation, brain, and kidneys. At the bedside, the red flags are new confusion, fast breathing, low blood pressure, a racing or weak pulse, clammy skin, and little urine. And not every patient runs hot. Some shiver or feel very cold.

4:33 Then there’s lactate. Lactate rises when tissues are under-perfused, but also from the stress response itself, and from epinephrine. It isn’t a direct measure of perfusion, but a high or climbing lactate marks a sicker patient. And a normal lactate doesn’t rule sepsis out. The 2026 update calls sepsis a clinical diagnosis, not ruled in or out by any single test.

The Hour-1 bundle, step by step 5:00

5:03 Once you suspect sepsis, the clock starts. This is the Hour-1 bundle. Start all five steps right away. Some take longer than an hour to finish.

5:14 Step one: measure lactate, and remeasure it if the first value is above 2. Surviving sepsis 2021 suggests measuring lactate: a weak recommendation, with low quality evidence. 2026 keeps it as a conditional suggestion. Step two: blood cultures before antibiotics, without delaying the antibiotics.

5:39 In 2021 that was a best practice statement. The 2026 update makes it a strong recommendation: as soon as possible, ideally before antimicrobials. Step three: broad-spectrum antibiotics. For possible septic shock, or a high likelihood of sepsis, the 2021 guideline recommends antimicrobials immediately, ideally within 1 hour of recognition.

6:06 That’s strong. If sepsis is only possible and there’s no shock, assess quickly, and if concern persists, give antibiotics within 3 hours. Step four: for low blood pressure, or a lactate of 4 or more, begin 30 mL/kg of crystalloid. The guideline says at least 30 mL/kg within the first 3 hours: weak in 2021, conditional in 2026.

6:35 The 2026 update adds a remark: with a BMI over 30, the volume can be based on adjusted or ideal body weight. Step five: if the patient is hypotensive during or after fluids, start a vasopressor to keep the MAP at 65 or higher.

Fluids, vasopressors and MAP targets 6:54

6:56 Let’s go deeper on fluids and pressors. For the fluid itself, guidelines suggest balanced crystalloids, like lactated Ringer’s, over normal saline. Then keep reassessing: dynamic measures, like a passive leg raise, over exam or static numbers alone, with capillary refill time as an adjunct. The goal is to avoid both under, and over-resuscitation.

7:21 For pressors, norepinephrine is first line: a strong recommendation in 2021 and 2026. If norepinephrine doses keep climbing, guidelines suggest adding vasopressin, usually around 0.25 to 0.5 mcg/kg/min of norepinephrine. If the MAP is still inadequate, epinephrine can be added next. And don’t wait for a central line. Guidelines suggest starting vasopressors peripherally rather than delaying.

7:51 Watch that IV site closely: norepinephrine leaking into tissue can cause necrosis, and the label calls for phentolamine. The initial MAP target is 65: a strong recommendation. And for patients 65 and older, the 2026 update suggests an initial MAP range of 60 to 65, over higher ranges.

Steroids, source control, de-escalation 8:15

8:18 Three more pieces round out treatment. Steroids. For septic shock with an ongoing need for vasopressors, the 2021 guideline suggests IV corticosteroids. Typically hydrocortisone, 200 mg a day, started once norepinephrine or epinephrine reaches 0.25 mcg/kg/min, at least 4 hours in.

8:42 The 2026 update still suggests IV corticosteroids for septic shock. Source control. Find the source fast, like an abscess to drain or an infected line to remove, and fix it as soon as it’s practical. The 2026 update suggests early source control, ideally within 6 hours of diagnosis.

9:04 And antibiotics need a plan to step down: review them daily, and narrow once cultures name the organism. Procalcitonin, plus clinical judgment, can help decide when to stop antibiotics, but not when to start.

Monitoring on the unit and for medics 9:19

9:22 So what does that mean on your shift? Trend vital signs, mental status, and urine output, and recheck the lactate if it was high. Follow the MAP, with an arterial line as soon as practical, and check skin and capillary refill. Time-stamp every bundle step, and escalate early when the patient isn’t responding.

9:44 Medics, you’re often the first to see it. The 2026 update suggests a standard sepsis screening tool in ambulances and flights. Call a pre-alert so the hospital is ready, and give fluids and oxygen per your protocol. Antibiotics before the hospital, only where protocols allow. 2026 suggests them for septic shock, when hospital evaluation is over an hour away.

Three exam traps 10:09

10:12 Three exam traps. Trap one: waiting on cultures. Draw them first if you can, but never let them delay the antibiotics. Trap two: trusting a normal blood pressure, or a negative qSOFA. Sepsis can be there before the pressure falls, so look for new confusion, and other organ trouble. Trap three: holding the vasopressor until a central line is in. A peripheral start is fine while you watch the site.

Recap 10:42

10:45 Recap. Sepsis is organ dysfunction from a dysregulated response to infection. Screen with NEWS, MEWS, or SIRS, not qSOFA alone, and look for organ trouble. Start the Hour-1 bundle: lactate, cultures, antibiotics, fluids, and a pressor for a MAP under 65.

11:06 Then reassess, control the source, and step the antibiotics down. RN Basics. Free on Google Play, and at rnbasics.com.