Original ContributionHypotension from spinal anesthesia in patients aged greater than 80 years is due to a decrease in systemic vascular resistance
Introduction
Hip fracture in elderly patients is associated with high rates of morbidity and mortality [1]. Although spinal anesthesia has several benefits [2], [3], spinal anesthesia-induced hypotension may lead to myocardial ischemia [4] and a reduction in middle cerebral artery velocity caused by impaired cerebral autoregulation [5]. Spinal anesthesia-induced hypotension is due to a decrease in systemic vascular resistance (SVR) associated with sympathetic block and vasodilation [6], [7], [8], especially when the sensory block level spreads to T5 or greater [9]. The hypotension is also due to a decrease in cardiac output (CO) with redistribution of the central volume to the lower extremities and splanchnic beds. However, Rooke et al [6] argued that the primary mechanism of spinal anesthesia-induced hypotension was a decrease in SVR while CO is preserved, even in patients with poor left ventricular function. Crystalloid intravascular volume administration prevents a decrease in CO regardless of preloading [10] or coloading [11], [12], [13] in spinal anesthesia. Although these reports targeted elderly patients, mean patient age in these reports ranged from 60 to 74 years; middle-aged patients also were included in some studies. The main aim of our study was to determine whether a decrease in SVR or CO was the main etiology of spinal anesthesia- induced hypotension in elderly subjects (> 80 yrs of age).
Section snippets
Materials and methods
The study protocol was approved by the Human Ethics Review Committee of Kansai Denryoku Hospital and written, informed consent form was obtained. We investigated all anesthetic records from August 2008 to April 2010 for consecutive elderly patients (age > 80 yrs) who underwent hip fracture repair (intramedullary nail or compression hip screw) during spinal anesthesia.
Results
Based on a power analysis, 18 patients were estimated to be needed in the hypotension group. The 18th patient of the hypotension group was admitted in April 2010. In comparison, 44 patients were included in the nonhypotension group during the study period (between August 2008 and April 2010). Two patients were excluded from analysis due to the development of atrial fibrillation during the study period. Accordingly, we compared the perioperative factors of 18 patients in the hypotension group
Discussion
Spinal anesthesia-induced hypotension in elderly patients, similar to younger patients, is caused primarily by a decrease in SVR [6], [7], [8]. The decrease in SVR during the first 20 minutes after spinal anesthesia was significantly greater in the hypotension group than the nonhypotension group. On the other hand, CO was well maintained in both groups [10], [11], [12], [13], even though cardiac reserve is expected to diminish with age [14]. One possible mechanism for the maintenance of CO is
References (30)
- et al.
General versus regional anaesthesia for hip fracture surgery: a meta-analysis of randomized trials
Br J Anaesth
(2000) - et al.
Hypotension during subarachnoid anaesthesia: haemodynamic effects of ephedrine
Br J Anaesth
(1995) - et al.
Hypotension during subarachnoid anaesthesia: haemodynamic effects of colloid and metaraminol
Br J Anaesth
(1996) The aged cardiovascular risk patient
Br J Anaesth
(2000)- et al.
Prediction of fluid responsiveness in patients during cardiac surgery
Br J Anaesth
(2004) - et al.
Assessing fluid responsiveness during open chest conditions
Br J Anaesth
(2005) - et al.
Automated pulse pressure and stroke volume variations from radial artery: evaluation during major abdominal surgery
Br J Anaesth
(2009) - et al.
Abilities of pulse pressure variations and stroke volume variations to predict fluid responsiveness in prone position during scoliosis surgery
Br J Anaesth
(2010) - et al.
Meta-analysis: excess mortality after hip fracture among older women and men
Ann Intern Med
(2010) - et al.
Patient risk factors, operative care, and outcomes among older community-dwelling male veterans with hip fracture
J Bone Joint Surg Am
(2008)
Perioperative myocardial ischaemia in patients undergoing surgery for fractured hip randomized to incremental spinal, single-dose spinal or general anaesthesia
Eur J Anaesthesiol
The effect of spinal anesthesia on cerebral blood flow in the very elderly
Anesth Analg
Hemodynamic response and changes in organ blood volume during spinal anesthesia in elderly men with cardiac disease
Anesth Analg
Incidence and risk factors for side effects of spinal anesthesia
Anesthesiology
Crystalloid/colloid versus crystalloid intravascular volume administration before spinal anesthesia in elderly patients: the influence on cardiac output and stroke volume
Anesth Analg
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2014, British Journal of AnaesthesiaCitation Excerpt :The latter has been denied by other studies.48 51–53 Changing doses of inotropes, vasopressors, or vasodilators, which is commonly done in clinical practice, can thus transiently change FloTrac/Vigileo™ compared with thermodilution CO, but a slow response of the latter to detect rapid changes in CO cannot always be excluded.5 7 8 25 26 35 36 40 41 47 53 61–66 An early study15 reported a concordance of 59% with intermittent thermodilution-derived CO for changes <15% in a mixed patient population.