Treatment of Hyponatremia in Patients with Acute Neurological Injury.

BACKGROUND: Little data exist regarding the practice of sodium management in acute neurologically injured patients. This study describes the practice variations, thresholds for treatment, and effectiveness of treatment in this population. METHODS: This retrospective, multicenter, observational study identified 400 ICU patients, from 17 centers, admitted for ≥48 h with subarachnoid hemorrhage (SAH), traumatic brain injury (TBI), intraparenchymal hemorrhage, or intracranial tumors between January 1, 2011 and July 31, 2012. Data collection included demographics, APACHE II, Glascow Coma Score (GCS), serum sodium (Na+), fluid rate and tonicity, use of sodium-altering therapies, intensive care unit (ICU) and hospital length of stay, and modified Rankin score upon discharge. Data were collected for the first 21 days of ICU admission or ICU discharge, whichever came first. Sodium trigger for treatment defined as the Na+ value prior to treatment with response defined as an increase of ≥4 mEq/L at 24 h. RESULTS: Sodium-altering therapy was initiated in 34 % (137/400) of patients with 23 % (32/137) having Na+ >135 mEq/L at time of treatment initiation. The most common indications for treatment were declining serum Na+ (68/116, 59 %) and cerebral edema with mental status changes (21/116, 18 %). Median Na+ treatment trigger was 133 mEq/L (IQR 129-139) with no difference between diagnoses. Incidence and treatment of hyponatremia was more common in SAH and TBI [SAH (49/106, 46 %), TBI (39/97, 40 %), ICH (27/102, 26 %), tumor (22/95, 23 %); p = 0.001]. The most common initial treatment was hypertonic saline (85/137, 62 %), followed by oral sodium chloride tablets (42/137, 31 %) and fluid restriction (15/137, 11 %). Among treated patients, 60 % had a response at 24 h. Treated patients had lower admission GCS (12 vs. 14, p = 0.02) and higher APACHE II scores (12 vs. 10, p = 0.001). There was no statistically significant difference in outcome when comparing treated and untreated patients. CONCLUSION: Sodium-altering therapy is commonly employed among neurologically injured patients. Hypertonic saline infusions were used first line in more than half of treated patients with the majority having a positive response at 24 h. Further studies are needed to evaluate the impact of various treatments on patient outcomes.

Awakening and withdrawal of life-sustaining treatment in cardiac arrest survivors treated with therapeutic hypothermia*.

OBJECTIVES: To characterize the prevalence of withdrawal of life-sustaining treatment, as well as the time to awakening, short-term neurologic outcomes, and cause of death in comatose survivors of out-of-hospital resuscitated cardiopulmonary arrests treated with therapeutic hypothermia. DESIGN: Single center, prospective observational cohort study of consecutive patients with out-of-hospital cardiopulmonary arrests. SETTING: Academic tertiary care hospital and level one trauma center in Minneapolis, MN. PATIENTS: Adults with witnessed, nontraumatic, out-of-hospital cardiopulmonary arrests regardless of initial electrocardiographic rhythm with return of spontaneous circulation who were admitted to an ICU. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The study cohort included 154 comatose survivors of witnessed out-of-hospital cardiopulmonary arrests who were admitted to an ICU during the 54-month study period. One hundred eighteen patients (77%) were treated with therapeutic hypothermia. The mean age was 59 years, 104 (68%) were men, and 83 (54%) had an initial rhythm of ventricular tachycardia or fibrillation. Only eight of all 78 patients (10%) who died qualified as brain dead; and 81% of all patients (63 of 78) who died did so after withdrawal of life-sustaining treatment. Twenty of 56 comatose survivors (32%) treated with hypothermia who awoke (as defined by Glasgow Motor Score of 6) and had good neurologic outcomes (defined as Cerebral Performance Category 1-2) did so after 72 hours. CONCLUSIONS: Our study supports delaying prognostication and withdrawal of life-sustaining treatment to beyond 72 hours in cases treated with therapeutic hypothermia. Larger multicenter prospective studies are needed to better define the most appropriate time frame for prognostication in comatose cardiac arrest survivors treated with therapeutic hypothermia. These data are also consistent with the notion that a majority of out-of-hospital cardiopulmonary arrest survivors die after a decision to withdrawal of life-sustaining treatment and that very few of these survivors progress to brain death.

Impact of intraoperative cefazolin on postoperative seizures after elective repair of unruptured cerebral aneurysm.

PURPOSE: The impact of intraoperative cefazolin on postoperative seizures after elective repair of an unruptured cerebral aneurysm was evaluated. METHODS: Chart review of a prospectively accrued database was performed for patients admitted from January 1, 2003, through December 31, 2013. Patients were included in the study if they underwent elective repair of an unruptured aneurysm with surgical clipping or wrapping. The primary objective was to determine if the use of cefazolin increased patients' odds of having a seizure within six hours of surgical intervention. Univariate comparisons were conducted on all variables for patients who received cefazolin and patients who were treated with other antibiotics. Multivariable logistic regression was performed to assess the impact of cefazolin administered intraoperatively on postoperative seizures, while accounting for other covariates. RESULTS: Of the 520 patients included, 53 (10.2%) patients developed seizures within six hours after surgery. A total of 439 (84.4%) patients received cefazolin intraoperatively. There were no differences in baseline characteristics between the patients who received cefazolin compared with those who did not. The frequency of seizures did not significantly differ between patients treated with cefazolin versus other antibiotics (11.2% versus 4.9%, respectively; p = 0.08). Multivariable regression revealed that the use of cefazolin did not increase the odds of having a seizure postoperatively compared with patients treated with other antibiotics (odds ratio, 2.4; 95% confidence interval, 0.82-7.15). CONCLUSION: No relationship was found between the intraoperative use of cefazolin and the development of seizures during the six hours after the repair of unruptured cerebral aneurysms.

Randomized controlled evaluation of an insulin pen storage policy.

PURPOSE: Results of a quality-improvement project to enhance safeguards against "wrong-pen-to-patient" insulin pen errors by permitting secure bedside storage of insulin pens are reported. METHODS: A cluster-randomized controlled evaluation was conducted at an academic medical center to assess adherence with institutional policy on insulin pen storage before and after implementation of a revised policy allowing pen storage in locking boxes in patient rooms. In phase 1 of the study, baseline data on policy adherence were captured for 8 patient care units (4 designated as intervention units and 4 designated as control units). In phase 2, policy adherence was assessed through direct observation during weekly audits after lock boxes were installed on intervention units and education on proper insulin pen storage was provided to nurses in all 8 units. RESULTS: Phase 1 rates of adherence to insulin pen storage policy were 59% in the intervention units and 49% in the control units (p = 0.56). During phase 2, there was no significant change from baseline in control unit adherence (67%, p = 0.26), but adherence in intervention units improved significantly, to 89% (p = 0.005). Common types of observed nonadherence included pens being unsecured in patient rooms or nurses' pockets or left in patient-specific medication drawers after patient discharge. CONCLUSION: An institutional policy change permitting secure storage of insulin pens close to the point of care, paired with nurse education, increased adherence more than education alone.

Evaluation of a Nurse-Managed Insulin Infusion Protocol.

BACKGROUND: The purpose of this study was to evaluate the performance of an insulin infusion protocol targeting a blood glucose (BG) level of 140-180 mg/dL and to characterize protocol adherence. MATERIALS AND METHODS: This was a retrospective observational cohort study including patients for whom the protocol was ordered from January 2012 to May 2013. Performance metrics were assessed in all patients and in patients with an initial BG level of ≥200 mg/dL. Protocol adherence was assessed in a random subset of 50 patients without hypoglycemia and in all hypoglycemic patients. RESULTS: In patients with an initial BG level of ≥200 mg/dL, the mean time to goal was 7.1 h. The rate of decline of BG level in the first 6 h was 16.4 mg/dL/h. Mean BG level was 167 mg/dL, with 43.9% of BG values within goal and 80.3% between 80 and 199 mg/dL. The rate of hypoglycemic events was 0.14 per 100 h. The mean protocol violation rate was higher in patients with hypoglycemia compared with those without (39.8 vs. 23.5 per 100 h, P = 0.002), and 60.7% of hypoglycemic events were attributable to protocol violations. The protocol violation rate (42.8 vs. 17.6 per 100 h; P < 0.001) and the odds of hypoglycemia (odds ratio = 5.2; 95% confidence interval, 1.6, 16.5) were higher in the cardiac surgery patients compared with other patients. CONCLUSIONS: This protocol provides adequate BG control within the clinically acceptable range of 80-199 mg/dL but not within the narrower range of 140-180 mg/dL, with a low incidence of hypoglycemia. Risk factors for hypoglycemia and barriers to protocol adherence in the cardiac surgery population should be elucidated.

Comparison of free fraction serum valproic acid concentrations between inpatients and outpatients.

PURPOSE: The differences in free fraction serum valproic acid concentrations between inpatients and outpatients were compared, and factors associated with therapeutic discordance were evaluated. METHODS: This retrospective, single-center, cross-sectional study included patients with both a free and a total valproic acid concentration drawn within 30 minutes of each other between January 7, 2003, and June 1, 2011. Serum valproic acid concentrations were stratified by admission status (inpatient versus outpatient). In the primary analysis, for patients who had multiple paired concentrations drawn, one free valproic acid level and one total valproic acid level (i.e., one pair) were chosen at random for each inpatient. Information regarding patient demographics, laboratory data, and concomitant medication therapy was collected. Single and multivariable logistic regressions were performed to determine the odds of therapeutic discordance. RESULTS: During the study period, inpatient concentrations were measured in 220 patients, and outpatient concentrations were measured in 41 patients. The median total valproic acid concentration in the inpatient group was significantly lower than that in the outpatient group (54 µg/mL versus 83 µg/mL, p < 0.001). The median free fraction of inpatient levels was nearly twice as high as that of outpatient levels (28.8% versus 15.5%, p < 0.001). Levels drawn in inpatients were therapeutically discordant 63% of the time compared to only 19% in outpatients (p < 0.001). Multivariable logistic regression identified low albumin as an independent risk factor for therapeutic discordance. CONCLUSION: The median free fraction of valproic acid was significantly higher in inpatients than in outpatients. Low albumin concentration was a predictor of discordance between free and total valproic acid concentrations.