In-Water Resuscitation, Is It Worthwhile?
Authors: David Szpilman, Márcio Soares
DOI / Source: https://doi.org/10.1016/j.resuscitation.2004.03.017
Date: 14 March 2004
Reading level: Beginner
Why This Matters for Freedivers
Most freediving accidents are hypoxia-driven, so time matters. This paper supports a simple idea: if someone isn’t breathing, starting effective ventilation sooner (even before reaching shore) can improve survival. It also highlights the hard truth that long no-breathing times strongly predict poor outcomes, reinforcing why fast rescue, fast ventilation, and good supervision are everything.
Synopsis
If you find someone in the water who isn’t breathing, you face a brutal decision: do you start rescue breaths immediately (in the water), or do you rush them to shore first and start there? This paper looks at real drowning rescues and asks whether “in-water resuscitation” (IWR)—basically providing ventilation while still in the water—improves outcomes.
The authors reviewed lifeguard rescues of non-breathing drowning victims along the coast of Rio de Janeiro over several years. They compared two groups: - IWR group: lifeguards started ventilation in the water. - No-IWR group: resuscitation began only after reaching shore.
The difference in survival was dramatic. The IWR group had much lower mortality than the no-IWR group. The reason is simple: in drowning, the main problem is oxygen starvation, and every minute without breathing increases brain injury risk. Starting ventilation earlier shortens the “no-oxygen” window.
But the paper also shows the uncomfortable trade-off: among the people who survived after IWR, a significant number still had severe neurological damage. That doesn’t mean IWR is “bad”—it means that some victims were already too far into the hypoxic timeline when they were found, and early ventilation can save a life without always saving the brain perfectly.
The strongest predictor of a poor outcome wasn’t the technique itself—it was how long the victim was in cardiopulmonary arrest (CPA) before ventilation started. In this dataset, once CPA duration went beyond roughly 14 minutes, outcomes were uniformly poor (death or severe neurological injury). The authors conclude that delaying resuscitation is associated with worse outcomes, IWR can increase the chance of survival in appropriate conditions, and rescuers should balance potential benefit against the danger of attempting ventilation in hazardous water. They also propose a practical decision-making algorithm to guide when IWR makes sense.
Abstract
Objective: To compare outcomes when ventilation is started immediately in the water versus delaying resuscitation until the victim is brought to shore.
Methods: Retrospective analysis of non-breathing drowning victims rescued by lifeguards. Cases were grouped by whether in-water resuscitation (IWR) was attempted. Poor outcome was defined as death or severe neurological damage.
Results: Survival was substantially higher when IWR was performed, but a portion of survivors still developed severe neurological injury. In analysis, IWR was associated with a lower likelihood of death, while longer estimated cardiopulmonary arrest duration strongly predicted poor outcome. In this series, every case with cardiopulmonary arrest duration greater than about 14 minutes had a poor outcome.
Conclusion: Delaying ventilation was associated with worse outcomes. In-water ventilation may improve survival in selected rescues, but decisions should consider time without breathing and rescuer safety.