Lightheadedness

Abstract: Patient O.T. is a 26-year-old white woman who works in the music industry. She was diagnosed with pneumonia and treated with inhalers. Shortly afterward, she developed spells of tachycardia. Her episodes of tachycardia were primarily associated with upright posture. In addition to rapid palpitations, she complained of lightheadedness and presyncope on standing, intermittent stabbing chest pains (typically on standing), mental clouding with an inability to concentrate, severe fatigue, and exercise intolerance. Orthostatic vital signs recorded a supine heart rate (HR) of 73 bpm with a blood pressure (BP) of 103/72 mm Hg. After standing for 1 minute, her HR increased to 106 bpm with a BP of 109/80 mm Hg, and after 5 minutes, her HR was 122 bpm with a BP of 118/75 mm Hg. She was diagnosed with postural tachycardia syndrome (POTS). Under normal conditions, the assumption of upright posture effects an instantaneous shift of ≈500 mL of blood from the thorax to the lower abdomen, buttocks, and legs. There is a secondary shift of plasma volume (10% to 25%) out of the vasculature and into the interstitial tissue, which decreases venous return to the heart (preload), resulting in a transient decline in cardiac filling and BP. This unloads the baroreceptors and triggers a compensatory decrease in parasympathetic tone and an increase in sympathetic activation, with a resultant increase in HR and systemic vasoconstriction (countering the initial decline in BP). The net hemodynamic effect of transition to upright posture is a 10- to 20-bpm increase in HR, a negligible change in systolic BP, and a ≈5-mm Hg increase in diastolic BP. Orthostatic dysregulation occurs when this gravitational regulatory mechanism does not respond properly. Patients can present with orthostatic hypotension (seen in autonomic nervous system failure) or with orthostatic tachycardia (seen in POTS). Patients with POTS typically maintain (or …

Abstract: Balance disorders in elderly patients are associated with an increased risk of falls but are often difficult to diagnose because of comorbid chronic medical problems. We performed a cross-sectional study to determine the prevalence of unrecognized benign paroxysmal positional vertigo (BPPV) and associated lifestyle sequelae in a public, inner-city geriatric population. Dizziness was found in 61% of patients, whereas balance disorders were found in 77% of patients. Nine percent were found to have unrecognized BPPV. Multivariate analysis demonstrated that the presence of a spinning sensation and the absence of a lightheadedness sensation predicted the presence of unrecognized BPPV. Patients with unrecognized BPPV were more likely to have reduced activities of daily living scores, to have sustained a fall in the previous 3 months, and to have depression. These data indicate that unrecognized BPPV is common within the elderly population and has associated morbidity. Further prospective studies are warranted.

Abstract: Complex Regional Pain Syndrome (CRPS) is a disorder that can be accompanied by severe pain that is often both chronic and resistant to conventional therapy. Harbut and Correll previously reported the successful treatment of a 9-year case of intractable Type I CRPS with an intravenous inpatient infusion of ketamine in an adult female patient [[1]][1]. Objective. The purpose of this study was to ascertain if indeed the use of subanesthetic inpatient infusions of ketamine provide meaningful improvements in pain scores, and thus, quality of life, in patients suffering from CRPS. To achieve this objective we focused our analysis on the relief of pain obtained by patients undergoing this novel treatment option developed at Mackay Base Hospital, Queensland, Australia. Methods. Case notes of 33 patients whose CRPS pain was treated by the inpatient administration of a continuous subanesthetic intravenous infusion of ketamine were reviewed. The dose and duration of ketamine therapy and the degree and duration of relief obtained were recorded. Notable side effects were also recorded. The degree of relief obtained (immediately after the infusion) was assessed using pre- and posttreatment numeric pain scores. The duration of relief obtained (throughout the follow-up period) was analyzed using a Kaplan-Meier cumulative survival curve analysis. Results. A total of 33 patients with diagnoses of CRPS who had undergone ketamine treatment at least once were identified. Due to relapse, 12 of 33 patients received a second course of therapy, and two of 33 patients received a third. The degree of relief obtained following the initial course of therapy was impressive (N=33); there was complete pain relief in 25 (76%), partial relief in six (18%), and no relief in two (6%) patients. The degree of relief obtained following repeat therapy (N=12) appeared even better, as all 12 patients who received second courses of treatment experienced complete relief of their CRPS pain. The duration of relief was also impressive, as was the difference between the duration of relief obtained after the first and after the second courses of therapy. In this respect, following the first course of therapy, 54% of 33 individuals remained pain free for ≥3 months and 31% remained pain free for ≥6 months. After the second infusion, 58% of 12 patients experienced relief for ≥1 year, while almost 33% remained pain free for >3 years. The most frequent side effect observed in patients receiving this treatment was a feeling of inebriation. Hallucinations occurred in six patients. Less frequent side effects also included complaints of lightheadedness, dizziness, and nausea. In four patients, an alteration in hepatic enzyme profile was noted; the infusion was terminated and the abnormality resolved thereafter. Conclusion. This retrospective review suggests that limited subanesthetic inpatient infusions of ketamine may offer a promising therapeutic option in the treatment of appropriately selected patients with intractable CRPS. More study is needed to further establish the safety and efficacy of this novel approach. [1]: #ref-1