Orthostatic Hypotension Occurs Frequently in the First Hour After Anesthesia

Department of Anesthesia and Perioperative Medicine, The University of Western Ontario, London, Ontario, Canada
Anesthesia & Analgesia (Impact Factor: 3.47). 01/2004; 98(1):40-5, table of contents. DOI: 10.1213/01.ANE.0000093388.17298.90
Source: PubMed


Symptoms of orthostatic intolerance are common after general anesthesia and are associated with an increased risk of postoperative morbidity. The contribution of orthostatic hypotension (OH) has not been well defined. We conducted a head-up tilt test on patients after general anesthesia for minor surgery to assess the incidence of and risk factors for OH after general anesthesia. One-hundred-four patients were enrolled and were prospectively divided into four groups: older female, older male, young female, and young male. The incidence of OH was 76.0%, 72.0%, 45.5%, and 62.5% respectively and was associated with increasing age (P < 0.05) and posttest dizziness (P < 0.05). Body mass index, preoperative blood pressure, ASA class, anesthetic duration, IV fluid administration, and use of analgesics and antiemetics in the postanesthetic care unit were not different in subjects who demonstrated OH compared with those with a normotensive response. Subjects with OH after general anesthesia did not increase their heart rate and diastolic blood pressure with a head-up tilt which may have been caused by persistent effects of anesthetics on reflex cardiovascular control and/or bedrest-induced dysregulation of reflex cardiovascular control. We conclude that OH is common after general anesthesia for minor surgery and may be the major cause of postoperative orthostatic intolerance. IMPLICATIONS: Orthostatic hypotension, a failure to maintain blood pressure on assuming an upright posture, is common after general anesthesia for minor surgery and may be the major cause of postoperative orthostatic intolerance.

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Available from: Adrian W Gelb, Aug 13, 2014
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    • "Patients who are confined to bed or frail are frequently placed in Fowler's position instead of remaining supine to assist ambulation, monitor hemodynamics and facilitate breathing as well as routine activities such as eating or conversation (Carol et al., 2008; Her and Frost, 1999; Metzler and Harr, 1996; Potter, 2009; Rauen et al., 2009). On the other hand, such patients develop orthostatic hypotension because they cannot physically compensate quickly for the downward fluid shift caused by assuming an upright position (Bundgaard-Nielsen et al., 2009; Cowie et al., 2004; Metzler and Harr, 1996; Steinberg, 1980). Thus, to understand the most effective posture required to counteract the downward fluid shift while in Fowler's position should be clinically meaningful. "
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    • "There is minimal research in Korea regarding orthostatic intolerance in surgical patients using patient controlled analgesia, while most of the research has been on the prevention and treatment of nausea and vomiting caused by the administration of drugs when using patient controlled analgesia [5]. In research done in other countries, there has only been research on orthostatic intolerance for early ambulation and cardiovascular response [1] and on orthostatic intolerance occurring 1 hour after anesthesia related to sex and age [6], and after an exhaustive search, no studies were found on the relationship of orthostatic intolerance with opioid analgesics used in patient controlled analgesia. Especially, there is nearly no research on the orthostatic intolerance of postoperative patients using patient controlled analgesia. "
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