Sudden Cardiac Arrest Associated with Hemodialysis: A Community-Based Study.

Background: Individuals with end-stage renal disease may be at increased risk of sudden cardiac arrest (SCA) associated with dialysis therapy. However, community-based studies with comprehensive adjudication of SCA are lacking.

Methods: We conducted a community-based study using a case-case study design in a US population of ≈1 million. All SCA cases with chronic kidney disease (CKD) were ascertained prospectively (2002-2020). We reviewed EMS narratives and archived medical records from regional hospitals to capture patients dialysis history, schedules, and the timing of SCA events in relation to dialysis sessions. Among those on regular hemodialysis, individuals who suffered SCA during hemodialysis or within an hour after completing hemodialysis (Intradialytic/immediate post-HD [IIHD]) were compared to cases with SCA at other times (non-IIHD). Non-compliant individuals or those intolerant of dialysis were excluded.

Results: Out of 1,023 SCA cases with CKD, 195 (19.1%) were undergoing regular scheduled hemodialysis. Among these cases, 24.1% were IIHD SCA, while 75.9% occurred non-IIHD. The incidence of SCA during dialysis was 2.9 times higher than expected by chance. SCA events were more likely to occur on dialysis days (65.3% of events) vs. 34.7% events on the 4 off dialysis days (p<0.001). IIHD SCA had higher serum sodium (138.9±4.8 vs. 135.5±5.5 mmol/L, p=0.005), lower serum potassium (3.6±0.7 vs. 5.6±1.6 mmol/L, p<0.001), and higher bicarbonate levels (25.9±6.6 vs. 20.2±5.5 mmol/L, p<0.001) compared to their non-IIHD SCA counterparts. Regarding resuscitation details, IIHD SCA had a higher percentage of shockable rhythm (46.5 vs. 32.4%, p=0.09), witnessed collapse (85.1 vs. 53.4%, p<0.001), bystander CPR (72.3 vs. 37.9%, p<0.001), return of spontaneous circulation (66.0 vs. 42.5%, p=0.005), and survival to hospital discharge (30.4 vs. 5.4%, p<0.001) compared to non-IIHD SCA.

Conclusions: In patients undergoing dialysis, SCA events were significantly more common on dialysis days, and 3-fold higher than expected by chance. We identified potential risk factors and survival outcome differences between IIHD vs. non-IIHD SCA groups that warrant future investigation.