Preoperative autonomic nervous system analysis may stratify the risk of hypotension after spinal anesthesia.

BACKGROUND: Studies on pregnant women undergoing cesarean delivery or elderly men scheduled for prostate brachytherapy have demonstrated the predictive value of heart rate variability (HRV) analysis for hypotension during spinal anesthesia. We conducted a prospective observational study to investigate if preoperative HRV analysis may have a role in identifying the risk of hypotension following spinal anesthesia in otherwise healthy patients. METHODS: The study investigated 47 ASA physical status I-II patients aged between 18-50 years that underwent subarachnoid anesthesia for lower abdominal or orthopedic scheduled surgery. ECG was recorded from all subjects before the subarachnoid block. We analysed the autonomic nervous system modulation, measured by HRV analysis. The variables that were be considered were preoperative HRV total power, low frequency (LF) and high frequency (HF) heart beat oscillations and LF/HF ratio. The LF/HF ratio was dichotomized according to the median for sensitivity analysis. The lowest arterial pressure value between spinal anesthesia and the end of surgery was recorded. RESULTS: The median LF/HF before anesthesia was 2.3. We considered two groups of 23 (LF/HF<2.3, group LOW) and 24 (LF/HF>2.3, group HIGH) patients respectively. Both groups had similar baseline demographic and hemodynamic variables. A high preoperative sympathetic outflow and loss of vagal modulation, as stated by LF/HF>2.3, was correlated with a relative risk of 7.7 (95%CI 1.04 to 56.6, p=0.023) of post-spinal hypotension. CONCLUSIONS: Preoperative analysis of autonomic nervous system modulation might be useful to stratify the risk of post-spinal hypotension and it might indicate the need for careful monitoring or prophylactic fluids.

[Latex allergy]. / Allergia al lattice.

The incidence of latex allergy has increased in the last decade in particular for medical and health care staff. The "L. Sacco" Hospital in Milan has developed an organisational model for dealing with clinical problems of patients allergic to latex who need to be admitted in hospital. Guidelines have been drawn up to handle the problem of latex allergy in hospital. An Interdisciplinary Working Group has systematically re-examined the epidemiological, etiopathogenetic, clinical diagnostic and therapeutic aspects of this important medical problem. This last topic has been particularly developed to facilitate doctors with emergency drugs. Nevertheless the most efficient method against the sensitisation is the elimination and reduction in hospital of the allergens causing the disease.

[The use of the Bullard laryngoscope]. / L'impiego del laringoscopio di Bullard.

Eighty patients were submitted to orotracheal intubation with adult bullard laryngoscope blade. Use and advantages are described, especially in difficult intubation.

[Importance of pupillary and photomotor reflexes in cardiac resuscitation]. / Importanza dei riflessi pupillari durante la rianimazione cardiocircolatoria.

The Authors present twenty cases of cardiac arrest which underwent cardio-respiratory resuscitation. The study of pupillary diameter and photomotor reflex are of easy detection and may be of relevant prognostic value during the resuscitation itself.