On May 30, 1984, Mardell E. Sanders brought this medical malpractice action individually, as executor of the Ivan T. Sanders estate, and as next friend of Vicky J. Sanders and Byron Ivan Sanders. Mardell is Ivan’s widow and Vicky’s and Byron’s mother. Defendants Thomas D. Ghrist, individually, and Thomas D. Ghrist, a professional corporation, responded with general denials. A jury trial resulted in a defendants’ verdict which was followed by plaintiffs’ unsuccessful motion for new trial. This appeal ensued and presents us with one issue: did the district court err in refusing to give a requested jury instruction? Our review is limited to the correction of legal errors. Iowa R.App.P. 4.
Dr. Ghrist is a medical doctor specializing in internal medicine diagnostic work. This case arises from allegations that Ghrist failed to properly diagnose and treat a malignant tumor which resulted in Ivan T. Sanders’ death. Among the theories under which plaintiffs sought damages was included Sanders’ lost chance to survive the disease. We first recognized this theory of recovery in
DeBurkarte v. Louvar,
The district court submitted the following instruction, number twelve, identical in part to the instruction on proximate cause that we sanctioned in DeBurkarte:
One who undertakes to render services to another which he should recognize is necessary for the protection of the other’s person is subject to liability to the other for physical harm resulting from his failure to exercise reasonable care to perform his undertaking if his failure to exercise such care increases the risk of such harm.
The part omitted from this instruction, however, read
for depriving her of the opportunity to receive early treatment and the chance of realizing gain in her life expectancy and physical harm and mental comfort.
Id. at 138 n. 3.
In its marshalling instruction on damages, number thirteen, the district court *522 limited plaintiffs’ potential recovery to the following elements of damage: (1) pain, suffering and mental anguish; (2) present value of Ivan Sanders’ estate “had he lived out the term of his natural life;” (3) present value of prospective support to his wife; and (4) present value of prospective services to his wife and children. According to this instruction, damages would be recoverable only if “shown by a preponderance of the evidence to have been sustained as a direct and proximate result of the incident alleged herein,” i.e., Ghrist’s negligence. No mention was made of the potential damages available under the lost chance of survival theory, notwithstanding plaintiffs’ request that the following sub-part, delineating the damages available under that theory, be included in the mar-shalling instruction:
The present worth of the opportunity to receive early treatment and the chance of realizing any resulting gain in life expectancy and physical or mental comfort.
This requested instruction is substantially identical to a portion of the instruction we sanctioned in
DeBurkarte. See
Parties to a lawsuit are entitled to have their legal theories submitted to a jury as long as they are supported by pleadings and substantial evidence.
E.g., Fratzke v. Meyer,
Instruction twelve and the instructions read as a whole fail to convey to the jury the legal theory on which a lost chance of survival recovery is based. This omission carried with it a likely misinterpretation of the law by the jury in applying both the instruction on proximate cause and the damages instruction. Regarding proximate cause, we believe the instructions as given permitted recovery if and only if the plaintiffs demonstrated by a preponderance that Sanders’ pain and suffering, as well as the lost value of his estate, support and services, were “a direct and proximate result” of Ghrist’s negligence. This is precisely the “all-or-nothing” liability we rejected in
Deburkarte. See
Instruction twelve also directed the jury that Ghrist is rendered “subject to liability ... for physical harm ... if his failure to exercise [reasonable] care increases the risk of such harm.” Accordingly, if Ghrist’s negligence increased the risk of Sanders’ “harm,”
i.e.,
failure to survive, Ghrist would be liable for the full amount of damages resulting from Sanders’ death. Liability under
DeBurkarte,
however, is not measured by the totality of the result ing physical harm but, rather, is limited to
*523
the reduction in the chance of surviving that harm.
In
DeBurkarte,
we agreed with the trial court’s instructions because those instructions clearly limited the damages available under the “lost chance” theory to the reduction in decedent’s chance of survival.
The legal theory supporting a recovery for lost chance of survival should be included as part of the proximate cause and the damages instructions. Plaintiffs’ motion for new trial should have been granted. Accordingly, we reverse the judgment of the district court and remand this case for a new trial.
REVERSED AND REMANDED.
