Propranolol block of epinephrine-induced hypokaliaemia in man

Predictive Value of Fibrin Fibrinogen Degradation Products-to-Potassium Ratio for Poor Functional Outcome in Patients with Aneurysmal Subarachnoid Hemorrhage: A Retrospective Case-Control Study

BACKGROUND

The relationship of fibrin(ogen) degradation products (FDPs) and potassium with the functional outcomes of patients with aneurysmal subarachnoid hemorrhage (aSAH) is still uncertain. This study aims to evaluate the predictive value of a novel combination biomarker, the FDP-to-potassium ratio (FPR), for poor functional outcomes in patients with aSAH.

METHODS

A total of 425 consecutive patients with aSAH at a single center were retrospectively enrolled in our study. An unfavorable outcome was defined as a modified Rankin Scale (mRS) score of 3-6 at 3 months after discharge. Univariate analysis and multivariable logistic regression were performed for baseline information and laboratory parameters recorded at admission. In addition, the receiver operating characteristic curve was plotted, and propensity score matching was performed based on the FPR.

RESULTS

On the basis of mRS grade, 301 patients were classified as having favorable outcomes, and 124 patients were assessed as having unfavorable outcomes. FPR levels were significantly correlated with mRS grade (r[Spearman] = 0.410; P < 0.001). Multivariate logistic regression analysis showed that age (odds ratio [OR] 1.043, 95% confidence interval [CI] 1.016-1.071; P = 0.002), white blood cell count (OR 1.150, 95% CI 1.044-1.267; P = 0.005), potassium (OR 0.526, 95% CI 0.291-0.949; P = 0.033), World Federation of Neurosurgical Societies grade (OR 1.276, 95% CI 1.055-1.544; P = 0.012), and FPR (OR 1.219, 95% CI 1.102-1.349; P < 0.001) at admission were independently associated with poor functional outcomes. The DeLong test showed that the area under the receiver operating characteristic curve of FPR was higher than that of age, white blood cell count, potassium, World Federation of Neurosurgical Societies grade, or FDP alone, indicating that FPR had better predictive potential than these other variables. After 1:1 propensity score matching (FPR ≥ 1.45 vs. FPR < 1.45), the rate of poor prognosis was still significantly increased in the high-FPR group (48/121 [39.7%] vs. 16/121 [13.2%], P < 0.001).

CONCLUSIONS

Fibrin(ogen) degradation product-to-potassium ratio is an independent predictor of poor outcomes for patients with aSAH and may be a promising tool for clinicians to evaluate patients' functional prognosis.

Serum glucose/potassium ratio as a clinical risk factor for predicting the severity and prognosis of acute traumatic spinal cord injury

OBJECTIVE

Acute traumatic Spinal cord injury (TSCI) is a devastating event that causes severe sensory and motor impairments as well as autonomic dysfunction in patients, yet relevant clinical biomarkers have not been established. This study aimed to determine the significance of the serum glucose/potassium ratio (GPR) in evaluating TSCI severity and predicting prognosis.

METHODS

An analysis of 520 clinical records of acute TSCI patients from January 2012 to June 2022 was conducted. The relationships between serum GPR and The American Spinal Injury Association Impairment Scale (AIS) grade 6-month post-trauma prognosis and the admission AIS grade were analyzed. To evaluate the discriminatory ability, a receiver operating characteristic curve (ROC) analysis was used. All methods were performed in accordance with the relevant guidelines and regulations.

RESULTS

Based on the initial assessment of AIS grade, 256 (49.2%) patients were categorized into the severe TSCI group (AIS A-B), and there was a significant correlation between the severe TSCI group and serum GPR (p < 0.001). Serum GPR was reduced in an AIS grade-dependent manner (R = - 0.540, p < 0.001). Of the 520 patients, 262 (50.4%) patients were classified as having a poor prognosis according to the AIS grade at discharge. Serum GPR was also reduced in an AIS grade at discharge-dependent manner (R = - 0.599, p < 0.001), and was significantly higher in the poor prognosis group compared to the good prognosis group (p < 0.001). Poor prognosis was significantly associated with sex (p = 0.009), severity of TSCI (p < 0.001), location of TSCI (p < 0.001), surgical decompression (p < 0.018), body temperature (p < 0.001), heart rate (p < 0.001), systolic arterial pressure (SAP) (p < 0.001), diastolic arterial pressure (DAP) (p < 0.001), serum GPR (p < 0.001), serum glucose (p < 0.001), serum potassium (p < 0.001), and white blood cell count (p = 0.003). Multivariate logistic regression analysis showed a significant correlation between poor prognosis and serum GPR (p = 0.023). The ROC analysis showed the area under the curve of serum GPR to be a poor predictor of prognosis in TSCI patients at 0.842 (95% confidence interval, 0.808-0.875).

CONCLUSION

There was a significant relationship between serum GPR and admission injury severity and the 6-month prognosis of acute TSCI patients. Serum GPR serves as a readily available clinical risk factor for predicting the severity and 6-month prognosis of acute traumatic spinal cord injury, which holds potential clinical significance for patients with TSCI.

Serum glucose and potassium ratio as a predictive factor for prognosis of acute intracerebral hemorrhage

Objective

The serum glucose/potassium ratio (GPR) is a potential prognostic predictor for acute brain injury-related diseases. We calculated the serum GPR in patients with acute intracerebral hemorrhage (ICH) and explored its prognostic value for long-term prognoses and ICH severity.

Methods

This retrospective cohort study consecutively included 92 patients with ICH and 92 healthy controls. The National Institutes of Health Stroke Scale (NIHSS) score, Glasgow coma scale (GCS) score, and hematoma volume were used to assess severity. A modified Rankin Scale score > 2 at 90 days post-stroke was defined as a poor outcome.

Results

The serum GPR was significantly higher in patients than controls. The serum GPR was weakly correlated with the NIHSS score, GCS score, and hematoma volume. The serum GPR, GCS score, and hematoma volume were independently associated with poor outcomes. In the receiver operating characteristic curve analysis, the serum GPR remarkably discriminated patients at risk of poor outcomes at 90 days. The serum GPR significantly improved the prognostic predictive capability of hematoma volume and tended to increase that of the GCS score.

Conclusion

Serum GPR is an easily obtained clinical variable for predicting clinical outcomes after ICH.

Usefulness of serum glucose and potassium ratio as a predictor for 30-day death among patients with severe traumatic brain injury

BACKGROUND

Serum glucose and potassium ratio (GPR) was recently found to be related to outcome of aneurysmal subarachnoid hemorrhage. This retrospectively study was to investigate the association of serum GPR with mortality in severe traumatic brain injury (sTBI).

METHODS

Clinical data were retrospectively reviewed of isolated sTBI patients admitted within 12 h after trauma between January 2014 and January 2019. We analyzed relationships between admission serum GPR and post-traumatic 30-day mortality in addition to admission Glasgow coma scale (GCS) scores. Discriminative ability was evaluated using area under receiver operating characteristic curve (AUC).

RESULTS

A total of 146 patients, of whom 37 (25.3%) died within 30 days following trauma, were included. Admission serum GPR emerged as an independent predictor for 30-day mortality (odds ratio, 5.256; 95% confidence interval (CI), 1.111-14.856) and overall survival (hazard ratio, 4.822; 95% CI, 1.157-12.870), with an AUC of 0.777 (95% CI, 0.693-0.835), which was equivalent to that of GCS scores (AUC, 0.831; 95% CI, 0.760-0.888; P = 0.179). There was a significant correlation between admission serum GPR and GCS scores (r² = 0.293).

CONCLUSIONS

Serum GPR in cases of sTBI is substantially associated with trauma severity and 30-day mortality. Therefore, the potential value of serum GPR for predicting short-term mortality of sTBI patients is favorable.

Serum Glucose and Potassium Ratio as Risk Factors for Cerebral Vasospasm after Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

Cerebral vasospasm is associated with poor prognosis in patients with aneurysmal subarachnoid hemorrhage (SAH), and biomarkers for predicting poor prognosis have not yet been established. We attempted to clarify the relationship between serum glucose/potassium ratio and cerebral vasospasm in patients with aneurysmal SAH.

METHODS

We studied 333 of 535 aneurysmal SAH patients treated between 2006 and 2016 (123 males, 210 females; mean age 59.7 years; range 24-93). We retrospectively analyzed the relationship between cerebral vasospasm grade and clinical risk factors, including serum glucose/potassium ratio.

RESULTS

Postoperative angiography revealed cerebral vasospasm in 112 patients (33.6%). Significant correlations existed between the ischemic complication due to cerebral vasospasm and glucose/potassium ratio (P < .0001), glucose (P = .016), and potassium (P = .0017). Serum glucose/potassium ratio was elevated in the cerebral vasospasm grade dependent manner (Spearman's r = 0.1207, P = .0279). According to the Glasgow Outcome Scale (GOS) score at discharge, 185 patients (55.5%) had a poor outcome (GOS scores 1-3). Serum glucose/potassium ratio was significantly correlated between poor outcome (GOS scores 1-3) and age (P < .0001), serum glucose/potassium ratio (P < .0001), glucose (P < .0001), potassium (P = .0004), white blood cell count (P = .0012), and cerebral infarction due to cerebral vasospasm (P < .0001). Multivariate logistic regression analyzes showed significant correlations between cerebral infarction due to cerebral vasospasm and serum glucose/potassium ratio (P = .018), glucose (P = .027), and potassium (P = .052).

CONCLUSIONS

Serum glucose/potassium ratio in cases of aneurysmal SAH was significantly associated with cerebral infarction due to cerebral vasospasm and GOS at discharge. Therefore, this factor was useful to predict prognosis in patients with cerebral vasospasm and aneurysmal SAH.

Serum glucose/potassium ratio as a clinical risk factor for aneurysmal subarachnoid hemorrhage

OBJECTIVE

Aneurysmal subarachnoid hemorrhage (SAH) can result in poor outcomes, and biomarkers for predicting poor prognosis have not yet been established. The aim of this study was to clarify the significance of the serum glucose/potassium ratio for predicting the prognosis of aneurysmal SAH.

METHODS

The authors retrospectively reviewed the records of 565 patients with aneurysmal SAH between 2006 and 2016. The patient group comprised 208 men and 357 women (mean age 61.5 years, range 10-95 years). A statistical analysis was conducted of the clinical and laboratory risk factors of poor outcome, including the serum glucose/potassium ratio.

RESULTS

On estimation of the initial assessment using Hunt and Kosnik (H-K) grading, 233 patients (41.2%) were classified as the severe SAH group (H-K Grade IV or V). There were significant correlations between the severe SAH group and serum glucose/potassium ratio (p < 0.0001). Serum glucose/potassium ratio was elevated in an H-K grade-dependent manner (Spearman's r = 0.5374, p < 0.0001). With the estimation of the Glasgow Outcome Scale (GOS) score at discharge, 355 patients (62.8%) were classified as poor outcome (GOS score 1-3). The serum glucose/potassium ratio was elevated in a GOS score at discharge-dependent manner (Spearman's r = 0.4006, p < 0.0001), and was significantly elevated in the poor outcome group compared with the good outcome group (GOS score 4 or 5; p = 0.0245). There were significant correlations between poor outcome and serum glucose/potassium ratio (p < 0.0001), age (p < 0.0001), brain natriuretic peptide levels (p = 0.011), cerebral infarction due to vasospasm (p < 0.0001), and H-K grade (p < 0.0001). Multivariate logistic regression analyses showed significant correlations between poor outcome and serum glucose/potassium ratio (p = 0.009).

CONCLUSIONS

In this study, the serum glucose/potassium ratio of patients with aneurysmal SAH at admission was significantly correlated with H-K grade and GOS score at discharge. Therefore, this ratio was useful for predicting prognosis of aneurysmal SAH, especially in severe cases.

The effect of patient-controlled intravenous analgesia on postoperative hypokalemia in patients undergoing laparoscopic cholecystectomy

PURPOSE

We investigated whether hypokalemia developed during the postoperative period and whether the use of intravenous patient-controlled analgesia (IV-PCA) could decrease the incidence of postoperative hypokalemia in patients who underwent laparoscopic cholecystectomy.

METHODS

Sixty patients undergoing laparoscopic cholecystectomy were randomly assigned to either IV-PCA (n = 30) or control (n = 30) groups. We measured serum potassium concentration at the outpatient department (T1), at 8:00 a.m. on the day of surgery (T2), at 6 h after the end of surgery (T3), and at 8:00 a.m. on the first (T4), second (T5), and third (T6) postoperative days. Serum potassium concentration, incidence of hypokalemia, mean blood pressure, heart rate, respiratory rate, and the patient-reported visual analogue scale score were compared within each group and between groups at each time point.

RESULTS

Serum potassium concentrations in all patients showed a significant decrease at T2-T4 compared to the preoperative concentration (T1). Serum potassium concentrations at T3 and T4 in the IV-PCA group were significantly higher than those in the control group. Also, the incidence of hypokalemia at T3 and T4 was significantly lower in the IV-PCA group. Mean blood pressure and heart rate were significantly lower in the IV-PCA group than in controls at T3 and T4.

CONCLUSIONS

The results show that hypokalemia developed during the perioperative period and the use of IV-PCA in patients undergoing laparoscopic cholecystectomy effectively decreased the degree and incidence of postoperative hypokalemia on the day of the operation and postoperative day one.

Hypokalemia in a Patient with Pheochromocytoma

OBJECTIVE

To report the occurrence of hypokalemia in a patient with pheochromocytoma.

METHODS

We present a case report and discuss the possible role of hyperepinephrinemia as a cause of hypokalemia.

RESULTS

A patient with pheochromocytoma had hypokalemia associated with vomiting, but hypokalemia recurred after repletion of potassium and cessation of vomiting. She had substantially increased epinephrine concentrations in the plasma and in the subsequently excised pheochromocytoma. Because evidence has shown that infusions of epinephrine induce hypokalemia in normal human subjects, the relationship between serum potassium and plasma epinephrine concentrations in 16 previous patients with pheochromocytoma and 4 patients with primary hyperepinephrinemia was studied. A significant negative correlation was noted.

CONCLUSION

The presence of hypokalemia and its potential role in predisposing to arrhythmias in patients with pheochromocytoma merit further study.

Epinephrine-induced hypokalemia: the role of beta adrenoceptors

Epinephrine was infused intravenously in 9 normal volunteers to plasma concentrations similar to those found after acute myocardial infarction. This study was undertaken on 3 occasions after 5 days of treatment with placebo or the beta-adrenoceptor antagonist, atenolol, which is relatively beta 1 selective, or timolol, which blocks both beta 1 and beta 2 receptors. Epinephrine increased the systolic blood pressure (BP), decreased the diastolic BP and increased the heart rate modestly. These changes were prevented by atenolol. However, after timolol the diastolic BP rose by +19 mm Hg and heart rate fell by -8 beats/min. Epinephrine caused the corrected QT interval to lengthen (0.36 +/- 0.02 to 0.41 +/- 0.06 second). No significant changes were found in the corrected QT interval when subjects were pretreated with atenolol or timolol. The serum potassium decreased from 4.06 to 3.22 mmol/liter after epinephrine. Serum potassium decreased to a lesser extent to 3.67 mmol/liter after atenolol and actually increased to 4.25 mmol/liter after timolol. In a further study with a similar design another nonselective beta blocker propranolol also increased potassium after epinephrine. While atenolol also prevented hypokalemia in this study, it did not block the beta 2-receptor mediated decrease in diastolic BP. Epinephrine-induced hypokalemia results from stimulation of a beta-adrenoceptor linked to membrane sodium/potassium adenosine triphosphatase causing potassium influx. This appears to be predominantly mediated by beta 2 receptors although beta 1 receptors may also play a part.

Metabolic and haemodynamic effects of increased circulating adrenaline in man. Effect of labetalol, an alpha and beta blocker

To simulate increased sympathoadrenal activity adrenaline was infused in normotensive subjects to achieve plasma adrenaline concentrations similar to those seen after myocardial infarction or hypoglycaemia. Adrenaline was infused after pretreatment for five days with labetalol 200 mg twice daily or placebo given in a random order. The rise in systolic blood pressure and the fall in diastolic blood pressure observed after the infusion of adrenaline (0.06 micrograms/kg/min) were prevented by labetalol and no increase in blood pressure was seen. Adrenaline infusion after pretreatment with placebo caused a profound fall in the serum potassium concentration (4.12-3.20 mmol(mEq)/l). Pretreatment with labetalol completely blocked adrenaline induced hypokalaemia (3.92-3.95 mmol(mEq)/l). Adrenaline induced T wave flattening and QTc prolongation were also prevented by labetalol. Thus labetalol can prevent the electrocardiographic, haemodynamic, and hypokalaemic effects of increased circulating adrenaline in man. The combination of alpha and beta blockade appears to be required to block the haemodynamic effects of adrenaline, and labetalol may, therefore, be useful in controlling both the metabolic and circulatory responses during increased sympathoadrenal activity.

Effect of intravenous adrenaline on electrocardiogram, blood pressure, and serum potassium

Increased catecholamines after myocardial infarction may contribute to the development of arrhythmias. We have infused adrenaline intravenously in nine normal volunteers to levels similar to those seen after myocardial infarction. Adrenaline caused an increase in systolic blood pressure, a decrease in diastolic blood pressure, and an increase in heart rate. Adrenaline also produced a decrease in T wave amplitude and an increase in the QTc interval. The serum potassium fell dramatically during the adrenaline infusion from a control value of 4.06 mmol/l to 3.22 mmol/l. Hypokalaemia after myocardial infarction is associated with an increased incidence of ventricular arrhythmias. Thus, circulating adrenaline may increase the frequency of arrhythmias both directly via changes in ventricular repolarisation and indirectly via adrenaline induced hypokalaemia.

Glucose-induced paradoxical hyperkalemia in patients with suppression of the renin-aldosterone system: prevention by sodium depletion

A paradoxical transitory elevation of serum potassium concentration after intravenous infusion of hypertonic glucose has been found in 6 renal and/or hypertensive patients with suppression of the renin-aldosterone system (RAS) while on high sodium intake. Sodium restriction induced a dramatic increase in plasma renin activity (PRA) and/or plasma aldosterone (PA) in every patient, a substantial fall in the elevated serum potassium levels in 4 out of the 6 patients and a marked increase in fractional potassium excretion. During sodium restriction the glucose-induced paradoxical transitory hyperkalemia was abolished. The study confirmed the important extrarenal influence of aldosterone in the maintenance of normal potassium level in the hyperosmolal extracellular fluid and showed that: i) high sodium intake may predispose to hazardous hyperkalemia after massive glucose loading in certain nondiabetic patients with liability to suppression of aldosterone; ii) sodium restriction abolishes the glucose-induced abnormal serum potassium response.

Cardiac effects of salbutamol-induced hypokalaemia in the conscious dog

1. Infusion of salbutamol (3.0 microgram/min after a bolus injection of 100 microgram) produced hypokalaemia in conscious dogs. 2. Measurement of arterial and coronary sinus potassium differences revealed no significant potassium loss from the heart with established hypokalaemia. 3. Shortly after the initial salbutamol bolus and before steady-state hypokalaemia had been achieved during salbutamol infusion, a prolongation of QTc occurred; this corresponded to a significant myocardial potassium of -0.12 mmol/l plasma. 4. Urinary electrolyte excretions indicated that the hypokalaemia was not due to urinary potassium loss. 5. It was deduced that potassium had moved intracellularly. No change in hydrogen ion status occurred to account for this. Pronounced rises in plasma insulin immunoreactivities during salbutamol infusions suggested this as one mechanism for potassium shifts.

Some metabolic and hormonal effects of salbutamol in man

The effect of i.v. infusion of a beta-adrenergic stimulant, salbutamol on blood insulin, glucose, lactate, phosphates, potassium and NEFA was studied in 9 normal subjects. The effect of the drug on the blood sugar and insulin response to i.v. glucose was also examined in 4 subjects. Salbutamol was followed by increases in insulin, glucose and lactate, and a fall in blood phosphorus and potassium. NEFA values did not change significantly. These effects of salbutamol were abolished by propranolol and may thus be attributed to its beta-adrenergic stimulating action. Salbutamol also induced a reduction in glucose tolerance, in spite of the presence of enhanced blood insulin levels.

Effect of propranolol on some adrenaline- and insulin-induced metabolic changes in man

The effect of propranolol on adrenaline- and insulin-induced changes in blood glucose pyruvate, lactate, phosphorus and potassium were examined in 29 apparently healthy volunteers. A slight, but significant reduction in adrenaline-induced hyperglycaemia was noted, along with suppression of both the increase in pyruvate and lactate and the decrease in phosphorus and potassium attributable to this catecholamine. There was no significant change in the blood glucose curve after insulin whereas insulin-induced increases in pyruvate and lactate were reduced by 44% +/- 17.7 (mean +/- SEM) and 78% +/- 5.4 respectively, and the fall in phosphorus by 48% +/- 3.1; the decrease in potassium, however, was not significantly modified. These findings suggest that changes in plasma pyruvate, lactate and inorganic phosphates induced by insulin, and regarded as espressions of its peripheral metabolism, are greatly dependent on the beta-adrenergic effect of the endogenous catecholamines released during the time when blood glucose values are low.