Israel Medical Association Journal

Objectives: To investigate the effect of hypoxemia and nocturnal glucose homeosatsis in non-diabetic patients with sleep apnea.

Methods: Seven non-diabetic patients with moderate to severe sleep apnea were connected to a continuous glucose-monitoring sensor while undergoing overnight polysomnography. Mean SpO₂ and percentage of time spent at SpO₂ < 90% were recorded. The correlation between mean glucose levels, the difference between consecutive mean glucose measurements (glucose variability) and the corresponding oxygen saturation variables were determined in each patient during REM[1] and non-REM sleep.

Results: No consistent correlation was found for the individual patient between oxygen saturation variables and glucose levels during sleep. However, a lower mean SpO₂ correlated with decreased glucose variability during sleep (r = 0.79, P = 0.034). This effect was primarily evident during REM sleep in patients with significant, compared to those with mild, oxygen desaturations during sleep (> 30% vs. < 10% of sleeping time spent with SpO₂ < 90%) (P = 0.03).

Conclusions: Severe nocturnal hypoxemia in non-diabetic patients with moderate to severe sleep apnea might affect glucose regulation primarily during REM sleep.

Background: Type 1 diabetes in humans is an autoimmune disease in which T cells target pancreatic islets of Langerhans, leading to the progressive destruction of the insulin-producing beta cells. Both genetic and environmental factors contribute to the development of autoimmune diabetes. The non-obese diabetic (NOD) mouse model of human type 1 diabetes demonstrates two missense mutations in the transient receptor potential vanilloid receptor-1 (TRPV1) gene.

Objectives: To investigate whether polymorphism in the TRPV1 gene may play a role in the predisposition to human type 1 diabetes.

Methods: We genotyped 146 Ashkenazi Jewish type 1 diabetic patients and 205 Ashkenazi Jewish healthy controls for the rs222747 (M315I), rs224534 (T469I) and rs8065080 (I585V) variants of the TRPV1 gene.

Results: There was a significant increase in the rs222747 (M315I) variant of the TRPV1 gene in the type 1 diabetes cohort compared to the control: rs222747 (M315I) homozygous: (61% vs. 48.3%, P = 0.02). Logistic regression analysis revealed that type1 diabetes was significantly associated with rs222747 (M315I), such that having diabetes increased the odds of rs222747 homozygosity (M315I) by 67.2%, odds ratio 1.6, 95% confidence interval 1.08–2.57, P < 0.02. No difference was found in the rs224534 (T469I) and rs8065080 (I585V) allelic variants. There was no difference in any of the TRPV1 variants by gender, age when type1 diabetes was diagnosed, body mass index, glycemic control, blood pressure, positive autoantibodies (ICA, GAD, IAA), and other autoimmune diseases.

Conclusions: Our study demonstrates that TRPV1 may be a susceptible gene for type 1 diabetes in an Ashkenazi Jewish population. These results should be replicated in the same ethnic group and in other ethnic groups.

Objectives: To assess the first national simulation-based communication skills training for neurosurgical residents.

Methods: Eight scenarios covering different aspects of neurosurgery were developed by our team: 1) obtaining informed consent for an elective surgery, 2) discharge of a patient following elective surgery, 3) dealing with an unsatisfied patient, 4) delivering news of intraoperative complications, 5) delivering news of a brain tumor to parents of a 5 year old boy, 6) delivering news of brain death to a family member, 7) obtaining informed consent for urgent surgery from the grandfather of a 7 year old boy with an epidural hematoma, and 8) dealing with a case of child abuse. Fifteen neurosurgery residents from all major medical centers in Israel participated in the training. The session was recorded on video and was followed by videotaped debriefing by a senior neurosurgeon and communication expert and by feedback questionnaires.

Results: All trainees participated in two scenarios and observed another two. Participants largely agreed that the actors simulating patients represented real patients and family members and that the videotaped debriefing contributed to the teaching of professional skills.

Conclusions: Simulation-based communication skill training is effective, and together with thorough debriefing is an excellent learning and practical method for imparting communication skills to neurosurgery residents. Such simulation-based training will ultimately be part of the national residency program.

Background: Spinal epidural abscess (SEA) is a rare disease with a potentially devastating outcome, and a reported incidence traditionally estimated at 0.2–2 cases/10,000 hospital admissions. Since the implementation in October 2007 of a program to increase medical personnel’s awareness of SEA, we have documented a sharp increase in the incidence of SEA at our medical center

Objectives: To investigate the cause of the increased incidence of SEA.

Methods: All cases diagnosed with SEA during the period 1998–2010 were retrospectively reviewed. Cases diagnosed before 2007 were compared with those diagnosed thereafter.

Results: From January 1998 to October 2007 SEA was diagnosed in 22 patients (group A), giving an annual incidence of 0.14–0.6 cases per 10,000 admissions. During the period November 2007 to April 2010, 26 additional patients were diagnosed (group B), yielding an incidence of 0.81–1.7 cases per 10,000 admissions (P < 0.01). The two groups did not differ significantly in epidemiological, clinical or laboratory characteristics, or in the causative bacteria isolated.

Conclusions: The threefold rise in the incidence of SEA observed at a tertiary medical center in Tel Aviv since November 2007 was not explained by different host characteristics or by more virulent bacterial isolates. We suggest that heightened awareness of the clinical presentation and timely utilization of MR imaging has resulted in more cases being identified. 

Background: Trans-catheter aortic valve implantation (TAVI) has emerged as a novel therapeutic approach for patients with severe tricuspid aortic stenosis (AS) not suitable for aortic valve replacement.

Objectives: To describe our initial single-center experience with TAVI in patients with "off-label" indications.

Methods: Between August 2008 and December 2011 we performed TAVI in 186 patients using trans-femoral, trans-axillary, trans-apical and trans-aortic approaches. In 11 patients (5.9%) TAVI was undertaken due to: a) pure severe aortic regurgitation (AR) (n=2), b) prosthetic aortic valve (AV) failure (n=5), c) bicuspid AV stenosis (n=2), and d) prosthetic valve severe mitral regurgitation (MR) (n=2).

Results: Implantation was successful in all: six patients received a CoreValve and five patients an Edwards-Sapien valve. In-hospital mortality was 0%. Valve hemodynamics and function were excellent in all patients except for one who received an Edwards-Sapien that was inside a Mitroflow prosthetic AV and led to consistently high trans-aortic gradients. No significant residual regurgitation in AR and MR cases was observed.
Conclusions: TAVI is a good alternative to surgical AV replacement in high risk or inoperable patients with severe AS. TAVI for non-classical indications such as pure AR, bicuspid AV, and failed prosthetic aortic and mitral valves is feasible and safe and may be considered in selected patients. 

Objective: To assess the ability of TREC and KREC counts to identify patients with combined T and B cell immunodeficiency in a pilot study in Israel.

Methods: We studied seven children born in Israel during the years 2010–2011 and later diagnosed with SCID, and an additional patient with pure B cell immunodeficiency. TREC and KREC in peripheral blood upon diagnosis and in their neonatal Guthrie cards were analyzed using real-time quantitative polymerase chain reaction, as were Guthrie cards with dried blood spots from healthy newborns and from normal and SCID-like controls.

Results: The first features suggestive of SCID presented at age 3.1 ± 2.4 months in all patients. Yet, the diagnosis was made 4.1 ± 2.9 months later. Their TREC were undetectable or significantly low at their clinical diagnosis and in their originally stored Guthrie cards, irrespective of the amount of their circulating T cells. KREC were undetectable in six SCID patients who displayed B cell lymphopenia in addition to T cell lymphopenia. KREC were also undetectable in one patient with pure B cell immunodeficiency.

Conclusions: TREC and KREC quantification are useful screening tests for severe T and B cell immunodeficiency. Implementation of these tests is highly important especially in countries such as Israel where a high frequency of consanguinity is known to exist. 

Objectives: To evaluate the predictive value regarding patients' survival once the diagnosis of “general deterioration” replaces an ICD-9 diagnosis upon re-admission.

Methods: In a retrospective cohort case-control study, we screened the records of patients re-admitted at least three times during the past 2 years. For each patient's death during the third hospitalization, we matched (for age and gender) a patient who survived the third hospitalization. We evaluated 14 parameters potentially accountable for increased risk of mortality, e.g., length of stay at each admission, interval to re-admission, etc. We applied a multifactorial analysis using logistic regression to predict the risk of mortality during the third hospitalization as potentially affected by the aforementioned parameters.

Results: The study included 81 study patients and 81 controls. Of the 14 parameters potentially explaining an increased risk of mortality during the third hospitalization, several were found to be statistically significant. The most significant was the diagnostic switch from a specific ICD-9 diagnosis on first admission to the non-specific diagnosis of “general deterioration” at the second hospitalization. In such cases, the risk of death during the third hospitalization was increased by 5300% (odds ratio = 54, P = 0.008). The increased risk of mortality was not restricted to patients with malignancy as their background diagnosis.

Conclusions: At re-admission, a switch from disease-specific diagnosis to the obscure diagnosis “general deterioration” increases the subsequent risk of mortality.

Objectives: To assess whether a new herbal-based potentially wake-promoting beverage is effective in counteracting somnolence and reduced post-lunch performance.

Methods: Thirty healthy volunteers were studied on three different days at the sleep clinic. On each visit they ate a standard lunch at noontime, followed by a drink of "Wake up®," 50 mg caffeine, or a placebo in a cross-over double-blind regimen. At 30 and 120 minutes post-drinking, they underwent a battery of tests to determine the effects of the beverage. These included: a) a subjective assessment of alertness and performance based on a visual analog scale, and b) objective function tests: the immediate word recall test, the digit symbol substitution test (DSST), and hemodynamic measurements. The results of the three visits were compared using one-way analysis of variance, with P < 0.05 considered statistically significant.

Results: In all performance tests, subjective vigilance and effectiveness assessment, both Wake up® and caffeine were significantly superior to placebo 30 minutes after lunch. However, at 2 hours after lunch, performance had deteriorated in those who drank the caffeine-containing drink, while Wake up® was superior to both caffeine and placebo. Blood pressure and pulse were higher 2 hours after caffeine ingestion, compared to both Wake up® and placebo.

Conclusions: These results suggest that a single dose of Wake up® is effective in counteracting the somnolence and reduced performance during the post-lunch hours. In the current study it had no adverse hemodynamic consequences.