Search PubMedSearch

Biomedical subjects

E H Winslow

Publications and source records attributed to E H Winslow.

At least 19 recordsLinked to original sources

Oxygen saturation and hemodynamic response in critically ill, mechanically ventilated adults during intrahospital transport.

BACKGROUND: Despite the frequency of intrahospital transport of critically ill patients, little research has been done on this topic and the findings are contradictory. OBJECTIVES: To describe arterial oxygen saturation by pulse oximetry, heart rate, heart rhythm, and systolic blood pressure and equipment problems in critically ill, mechanically ventilated adults during intrahospital transport. METHODS: The sample consisted of 36 critically ill, mechanically ventilated adults who required transport out of the intensive care unit for diagnostic testing or procedures within the hospital. Arterial oxygen saturation, heart rate, heart rhythm, and systolic blood pressure were measured at baseline, at least every 5 minutes during transport to and from the test site and at the test site, and every 5 minutes for 15 minutes after return to the unit. Descriptive statistics were used to analyze the data. RESULTS: Nineteen patients (53%) had clinically important changes in arterial oxygen saturation, heart rate, and/or systolic blood pressure. New cardiac arrhythmias developed in two patients. The clinically important changes occurred most frequently at the test/procedure site. Equipment problems such as monitor power failure and ventilator disconnection occurred during transport of 4 patients (11%). Total time out of ICU averaged 62 +/- 30 (range = 26 to 166) minutes. CONCLUSIONS: Transport outside the intensive care unit places the critically ill patient at additional risk. Although transport is often unavoidable, its risks versus benefits should be carefully and collaboratively evaluated for every patient prior to making the decision for transport.

Adult

The physiologic basis for continuous mixed venous oxygen saturation monitoring.

Critically ill patients often have conditions that reduce oxygen delivery and increase oxygen demand. Routine nursing care, such as suctioning, positioning, and bathing, also increases the patient's oxygen demand. If the patient's oxygen demand exceeds the supply, dysrhythmias, hypotension, altered level of consciousness, and other adverse responses can occur. We describe use of continuous monitoring of mixed venous oxygen saturation (SvO2) as a tool to assess the patient's supply/demand balance during nursing care. The physiology of oxygen transport is reviewed, and oxygen delivery, reserve, and consumption are defined. Conditions that decrease oxygen delivery and increase oxygen demand are discussed, and the effects on SvO2 are illustrated. With continuous SvO2 monitoring, critical care nurses can see the effect of their nursing care on the patient's oxygenation and can adjust their care according to the patient's tolerance.

Critical Care

Effects of endotracheal suctioning on mixed venous oxygen saturation and heart rate in critically ill adults.

The purpose of this multisite study was to determine the effects of endotracheal suctioning on mixed venous oxygen saturation (SvO2) and heart rate in 189 critically ill adults. One-pass, intermittent suction was applied for 10 or fewer seconds, with three prehyperoxygenation and three posthyperoxygenation breaths of 100% oxygen. Subjects at three hospitals (n = 127) underwent suctioning using hyperoxygenation with anesthesia bags and traditional suction catheters (open suction method). Subjects at one hospital (n = 62) underwent suctioning with hyperoxygenation by ventilator and in-line suction catheters (closed suction method). For subjects from all hospital sites combined, the SvO2 decreased from 67% to 64% (p = 0.001), a 4% change from baseline, and returned to baseline within 2 minutes. However, in subjects receiving the open method of suction, SvO2 dropped from 66% to 62% immediately after suctioning and returned to baseline within 4 minutes. In contrast, when the closed suction method was used, SvO2 rose from 67.7% to 67.86% immediately after suctioning, drifting upward to 71% for the next 2 minutes before dropping toward the baseline after 4 minutes. Mean heart rate increased from a baseline of 99 beats/min to 104 beats/min immediately after suctioning (p = 0.001), a 5% change from baseline, and gradually returned to baseline over the next 4 minutes. No significant differences were seen in heart rate between subjects having the open versus closed suction method. In conclusion, the closed suction method showed a higher SvO2 after endotracheal suctioning compared with the open suction method (p = 0.0001). Some form of hyperoxygenation before and after endotracheal suctioning is recommended.

Adult

Effects of a lateral turn on mixed venous oxygen saturation and heart rate in critically ill adults.

The purpose of this study was to determine the effects of a lateral turn on mixed venous oxygen saturation (SvO2) and heart rate in 183 critically ill adults. Mean SvO2 decreased from a baseline of 67% to 61% saturation (p less than 0.0001) immediately after turning and gradually returned to 66% saturation (p less than 0.002) within 4 minutes. Mean heart rate increased slightly from a baseline of 99 beats/min to 102 beats/min (p less than 0.0001) immediately after turning and decreased slightly to 101 beats/min (p less than 0.0004) within 4 minutes. These statistically significant changes in SvO2 and heart rate were not clinically significant for most patients. However, physiologic responses to turning were highly variable. SvO2 reductions of 25% or more from baseline, heart rate increases and decreases of 10 beats/min or more, and signs of activity intolerance occurred in some patients. Nurses should expect critically ill patients to have a decrease in SvO2 of approximately 9% of baseline and small changes in heart rate after turning. These changes should be transient, with SvO2 and heart rate gradually returning toward baseline levels during the next 4 minutes. If turning triggers large or prolonged changes in SvO2 or heart rate, prompt repositioning and evaluation are needed to prevent adverse effects.

Critical Care

Effects of a 1-minute back rub on mixed venous oxygen saturation and heart rate in critically ill patients.

In this study we evaluated mixed venous oxygen saturation (SvO2) and heart rate responses after a 1-minute back rub in 173 critically ill patients. The back rub was the third and last intervention in a study conducted in intensive care units at four hospitals. For this multiple-intervention study all patients were placed in a supine position to obtain baseline SvO2 and heart rate, then underwent suctioning via endotracheal tube, and were turned to a lateral position. After 15 minutes in a side-lying position, the subjects received a 1-minute back rub. Data were collected immediately after the back rub and at 1-minute intervals for 4 minutes. After the back rub, SvO2 decreased immediately from the mean baseline of 67% to 63% and gradually increased, returning to baseline by minute 4. The mean baseline heart rate of 99 beats/min increased to 103 beats/min immediately after the back rub and gradually decreased after massage, but remained higher than baseline by minute 4. Although the findings were statistically significant (p = 0.0001), these minimal physiologic changes do not represent clinical significance. Based on the findings, the back rub, a traditional nursing measure that can provide comforting touch, represented a minor stimulus affecting heart rate and oxygen demands in most critically ill patients. However, because of the variability found in heart rate and SvO2, individual responses need to be assessed.

Adult

Cognitive changes in chronic renal patients during hemodialysis.

The Number Connection Test (NCT) was used to assess cognitive functioning in 29 chronic renal patients receiving hemodialysis. The patients required an average of 81 seconds to complete the test before hemodialysis compared to 98 seconds during hemodialysis (difference = 17 seconds) (t = 3.29; p = .0027). These findings cannot be explained by test order, sex, age, number of years on dialysis, or duration of each dialysis treatment. This study suggests that renal patients may have decreased cognitive functioning during the hemodialysis treatment. The dialysis period, though a convenient and popular time for patient education, may not be the best time to teach patients. Additional research is needed to confirm these findings and to identify the best and worst times for patient education for hemodialysis patients.

Adult

The role of the nurse in patient education. Focus: the cardiac patient.

Although nursing perceives patient teaching as an essential function, there is significant disparity between policy and practice. The evidence cited shows that nurses are not doing effective, consistent patient teaching and are not perceived by patients and doctors as competent in patient teaching. It appears that nurses do not view patient teaching as a priority and that nurses are not held accountable for patient teaching. Patient teaching seems to be done only "if there is time." It is often done on an informal and largely voluntary basis by motivated nurses. Nurses must awaken to the fact that patient education is not a luxury, but a necessity if patients are to receive maximum benefit from today's knowledge of treatment, prevention, and control of disease. Multiple factors interfere with nurse's doing adequate patient teaching, including inadequate preparation to teach and discrepancies in acceptance of teaching as the nurse's role. These obstacles can be overcome; they must be overcome if nursing is to make a significant contribution toward quality health care.

Health Education