by Marjorie Sue Cole Vaughan

Institution: University of Arizona
Year: 1980
Keywords: Body temperature.; Hypothermia, Induced.; Postoperative care.
Record ID: 1511847
Full text PDF: http://hdl.handle.net/10150/282260


In the homeotherm, core body temperature (T(bc)) is considered one of the vital signs by which physiologic normality can be assessed. In persons who are unable to self-regulate T(bc), hypothermia (HT) can result. Recognition of HT as a potential physiologic problem especially in the adult postsurgical patient who is recovering from anesthesia has been acknowledged. Recovery room (RR) nurses daily manage the shivering patient who not only experiences increased oxygen demand, but who may also exhibit airway obstruction and increased somnolence as a result of HT. Thus, a primary nursing activity in the RR is to assist the patient in recovery from anesthesia and to facilitate his return toward normothermia. No study has delineated the frequency, temperature range, or duration of HT in adult RR postsurgical patients. Additionally, no data exist to support the effectiveness of current nursing heat treatments directed against mild to moderate degrees of HT. The present study addresses both of these issues. Hypothermia is defined as T(bc) of less than 36.0 degrees centigrade (°C). One hundred ninety-eight patients were randomly assigned to one of four treatment groups. Three groups received a form of external heat while the final group did not. Heat was applied with radiant heat lamps, thermal with bath blanket (warmed), and bath blankets (warmed) with change. The control group had one bath blanket at room temperature. The purposive, nonrandom sample consisted of consenting adults scheduled for various operative procedures. Previous approval for the protocol had been received from the Human Subjects Committee. In all patients requiring RR care, identifying and descriptive characteristics were recorded. Disposable tympanic membrane probes were used to assess T(bc) with measurements taken on RR admission and every 15 minutes thereafter until discharge. Descriptive statistical analyses demonstrated that 60 percent of the subjects (n = 118) were hypothermic on RR admission. Mean RR admission T(bc) and discharge T(bc) (mean ± standard error [range]) were 35.6°C ± 0.06 [32.5-37.5°C] and 36.3 ± 0.05 [33.5-38.0°C] respectively. Duration of HT averaged 47 ± 4 minutes. Eighteen percent of all subjects were discharged from the RR with T(bc) of less than 36.0°C. Among heat transfer treatment groups, one-way analysis of variance or group t-tests demonstrated no significant difference in the rate of T(bc) rise in the first hour of RR stay, T(bc) change every 15 minutes, change in T(bc) divided by RR time, or discharge T(bc). Statistical significance was set at p < .05). Aged subjects (≥ 60 years) compared to nonaged subjects (< 60 years) demonstrated significantly lower T(bc)'s on admission and throughout the mean RR stay (admission to +90 minutes; p < .05). Rate of T(bc) rise for aged subjects was not significantly different from nonaged subjects. In conclusion, RR nurses should be alert for HT in a significant number of adult postsurgical patients. Accurate monitoring of T(bc) is necessary particularly early during the RR stay.…