Situation: A 55-year-old man with chronic kidney disease (CKD) stage G5 caused by diabetes starts hemodialysis (HD) in a hospital dialysis unit. His access is an arteriovenous (AV) fistula in his left forearm, created 4 months ago. Before his first session, his blood urea nitrogen (BUN) is 128 mg/dL (45.7 mmol/L). At his third session, 2 hours into treatment, he complains of leg cramps and dizziness. His blood pressure is 84/50 mmHg (150/88 mmHg before dialysis), and his pulse is 108/min. He is alert and breathing comfortably. Which action should the nurse take FIRST?

Hypotension is the most common complication of hemodialysis and usually results from rapid fluid removal (ultrafiltration). The immediate step is to stop or reduce ultrafiltration and lower the head of the bed to restore venous return; the prescribed saline bolus follows if the pressure stays low. Cramps from rapid fluid removal improve as volume is restored.

Clinical situation A 55-year-old man on hemodialysis for CKD G5 due to diabetes develops intradialytic hypotension during his third session: BP has fallen from 150/88 mmHg predialysis to 84/50 mmHg, with compensatory tachycardia at 108/min. He is alert and breathing comfortably, but complains of leg cramps and dizziness. The priority is to interrupt the ongoing volume loss and improve venous return before adding volume.

Why hypotension happens on dialysis During hemodialysis, the machine removes plasma water by ultrafiltration. If fluid is pulled from the vascular compartment faster than it can be refilled from the interstitium, circulating blood volume falls, venous return to the heart drops, and cardiac output declines ^[1]. Normally the body compensates by increasing heart rate, myocardial contractility, and arteriolar tone; when these mechanisms are exhausted or blunted, blood pressure falls ^[1][2]. Patients with diabetes are especially vulnerable because autonomic dysfunction impairs the vasoconstrictor and heart-rate responses that would otherwise defend blood pressure during rapid fluid removal ^[2].

Why the first action is to stop fluid removal and lower the head of the bed The defining problem in intradialytic hypotension is hypovolemia caused by ongoing ultrafiltration ^[1][2]. Continuing to remove fluid while the patient is already hypotensive will further reduce preload and worsen organ hypoperfusion. Stopping or reducing ultrafiltration removes the cause of the falling blood pressure, and lowering the head of the bed uses gravity to shift blood toward the central circulation, increasing venous return and supporting cardiac output. This is the fastest intervention that directly addresses the mechanism of the hypotension.

Where the saline bolus fits A 0.9% sodium chloride bolus is an appropriate next step, but it is not the first action. Volume replacement works by expanding the intravascular space; however, if ultrafiltration continues at the same rate, the infused fluid is being removed almost as quickly as it is given. Stopping fluid removal must precede or accompany volume administration for the bolus to be effective. The sequence in practice is: stop ultrafiltration, position the patient, then give saline if the pressure remains low after the cause has been interrupted.

Leg cramps and their relationship to volume The patient’s calf cramps are a symptom of the same process. Rapid fluid removal reduces muscle perfusion and can cause dialysis-associated muscle cramps, which typically improve as intravascular volume is restored ^[1]. Massaging the calves and applying warm compresses may provide comfort, but they do not correct the underlying hypovolemia and should not delay the priority actions. Watch out! Treating the cramp without addressing the hypotension leaves the patient at risk for further volume loss and worsening perfusion.

Why rechecking in 15 minutes is not the first step Waiting to recheck blood pressure before acting is inappropriate when the clinical picture is already clear. A fall from 150/88 to 84/50 mmHg during dialysis, accompanied by dizziness and tachycardia, meets the definition of intradialytic hypotension and warrants immediate intervention . Delaying treatment to confirm the finding exposes the patient to continued ultrafiltration and the risk of myocardial stunning, cerebral hypoperfusion, and other end-organ injury ^[1][2].

Nursing priority framework The correct sequence follows the principle of addressing the cause before adding compensatory treatments. Key point! The first nursing action for intradialytic hypotension is to stop or reduce ultrafiltration and lower the head of the bed; saline is given afterward if the pressure remains low.

Action	Rationale	Priority
Stop fluid removal and lower head of bed	Removes the cause (ongoing ultrafiltration) and increases venous return by gravity	First
Give 0.9% sodium chloride bolus	Expands intravascular volume; effective only after ultrafiltration is stopped or reduced	Second
Massage calves and apply warm compresses	Comfort measure for cramps; does not correct hypovolemia	Later
Recheck BP in 15 minutes	Delays treatment in a patient with clear hypotension and ongoing volume loss	Not appropriate as first step

Clinical implications Intradialytic hypotension occurs in a substantial proportion of dialysis sessions and is associated with worse cardiovascular outcomes and mortality ^[1][2]. The ultrafiltration rate is a modifiable driver of these events, and management strategies increasingly focus on limiting excessive fluid removal and monitoring blood volume to prevent critical reductions in circulating volume ^[1][2]. For the nurse at the chairside, recognizing early signs such as dizziness, cramping, and a falling systolic pressure and responding immediately by stopping ultrafiltration and positioning the patient is the core safety intervention.