Monday, July 14, 2014

Regional anaesthesia and cancer metastases: the implication of local anaesthetics

E. G. VOTTA-VELIS et al.

Acta Anaesthesiologica Scandinavica

Volume 57, Issue 10, pages 1211–1229, November 2013

Clinical and basic science studies have demonstrated the anti-inflammatory properties of local anaesthetics. Recent studies have begun to unravel molecular pathways linking inflammation and cancer. Regional anaesthesia is associated in some retrospective clinical studies with reduced risk of metastasis and increased long-term survival. The potential beneficial effects of regional anaesthesia have been attributed mainly to the inhibition of the neuroendocrine stress response to surgery and to the reduction in the requirements of volatile anaesthetics and opioids. Because cancer is linked to inflammation and local anaesthetics have anti-inflammatory effects, these agents may participate in reducing the risk of metastasis, but their mechanism of action is unknown. We demonstrated in vitro that amide local anaesthetics attenuate tumour cell migration as well as signalling pathways enhancing tumour growth and metastasis. This has provided the first evidence of a molecular mechanism by which regional anaesthesia might inhibit or reduce cancer metastases.

Sunday, July 6, 2014



Technology  escalating impact on perioperative  care : Clinical,compliance and medicolegal considerations

Brian J Cammarata and Brian J Thomas
APSF newsletter,Volume 29N1 1-24 June 2014–07–06

Vignette

A 57 year old female presents for a laparoscopic cholecystectomy
Following the uneventful induction of general anesthesia, the patient is prepped and surgery begins.
Intraoperatively, the patient becomes acutely hypotensive and tachycardic.
Despites intravenous fluids and phenylephrine, the hypotension persists.
The patient is ultimately resuscitated but slow to awaken postoperatively.
MRI of the head reveals an ischemic infarction.
She regains consciousness on postoperative day 1, but has persistent right sided weakness
The spouse and the surviving children bring suit against the anesthesiologist for failing to appropriately treat the hypotension resulting in a cerebro vascular accident.
During discovery, the circulating nurse and scrub technician testify that the anesthesiologists was on her cell phone and checking e-mail immediately prior to the event.
Plaintiff's attorney subpoenaed the cell phone and hospital computer records validating the allegation.

Comments - Cell phone and hospital computer records are discoverable and may be admissible evidence at trial.
In this case, the anesthesiologist's defensible care is compromised by the proven allegation of electronic distraction during the anesthetic


A Randomized Trial of Epidural Glucocorticoid Injections for Spinal Stenosis

 Janna L. Friedly, M.D et al.

 N Engl J Med 2014; 371:11-21July 3, 2014

 In a double-blind, multisite trial, they randomly assigned 400 patients who had lumbar central spinal stenosis and moderate-to-severe leg pain and disability to receive epidural injections of glucocorticoids plus lidocaine or lidocaine alone. The patients received one or two injections before the primary outcome evaluation, performed 6 weeks after randomization and the first injection. 

 At 6 weeks, there were no significant between-group differences in the RMDQ score (adjusted difference in the average treatment effect between the glucocorticoid–lidocaine group and the lidocaine-alone group).

In the treatment of lumbar spinal stenosis, epidural injection of glucocorticoids plus lidocaine offered minimal or no short-term benefit as compared with epidural injection of lidocaine alone.


Tuesday, July 1, 2014



Adrenal response after trauma is affected by time after trauma and sedative/analgesic drugs.

Brorsson C, Dahlqvist P, Nilsson L, Thunberg J, Sylvan A, Naredi S
 Injury. 2014 Aug;45(8):1149-55

The aim of this study was to assess the early adrenal response after trauma.

METHODS:

Prospective, observational study of 50 trauma patients admitted to a level-1-trauma centre. Serum and saliva cortisol were followed from the accident site up to five days after trauma. Corticosteroid binding globulin (CBG), dehydroepiandrosterone (DHEA) and sulphated dehydroepiandrosterone (DHEAS) were obtained twice during the first five days after trauma. The effect of time and associations between cortisol levels and; severity of trauma, infusion of sedative/analgesic drugs, cardiovascular dysfunction and other adrenocorticotropic hormone (ACTH) dependent hormones (DHEA/DHEAS) were studied.

RESULTS:

There was a significant decrease over time in serum cortisol both during the initial 24h, and from the 2nd to the 5th morning after trauma. A significant decrease over time was also observed in calculated free cortisol, DHEA, and DHEAS. No significant association was found between an injury severity score≥16 (severe injury) and a low (<200nmol/L) serum cortisol at any time during the study period. The odds for a serum cortisol <200nmol/L was eight times higher in patients with continuous infusion of sedative/analgesic drugs compared to patients with no continuous infusion of sedative/analgesic drugs.

CONCLUSION:

Total serum cortisol, calculated free cortisol, DHEA and DHEAS decreased significantly over time after trauma. Continuous infusion of sedative/analgesic drugs was independently associated with serum cortisol <200nmol/L.


Intracranial pressure response after pharmacologic treatment of intracranial hypertension.

J Trauma Acute Care Surg. 2014 Jul;77(1):47-53.

Patients older than 17 years, admitted and requiring ICP monitoring between 2008 and 2010 at a high-volume urban trauma center, were retrospectively evaluated. Timing and dose of ICP-directed therapy were recorded from paper and electronic medical records. ICP data were collected automatically at 6-second intervals and from manual charts
A total of 117 patients met inclusion criteria; 450 treatments were administered when nursing records indicate an ICP greater than 20 mm Hg, while 968 treatments were given when ICP was greater than 20 mm Hg by automated data.
 Pharmacologic treatments identified include hypertonic saline (HTS), mannitol, barbiturates, and dose escalations of propofol or fentanyl infusions.
Treatment with HTS resulted in the largest ICP decrease of the treatments examined, with a 1-hour ICP reduction of 8.8/9.9 mm Hg (for a small/large dose) according to manual data and a reduction of 3.0/2.4 mm Hg according to automated data. Propofol and fentanyl escalations resulted in smaller but significant ICP reductions. Mannitol (n = 8) resulted in statistically insignificant trends down in the first hour but rebounded by the second hour after administration. The average ICP in the hour before medication administration was higher for barbiturates (27 mm Hg) and mannitol (32 mm Hg) than for the other interventions (18-19 mm Hg).

CONCLUSION:

ICP fell after administration of HTS, mannitol, or barbiturates and showed continued improvement after 2 hours. ICP fell initially after treatment with short-acting propofol and fentanyl but trended back up after 2 hours

Sunday, June 29, 2014



Anesthesia Technique, Mortality, and Length of Stay After Hip Fracture Surgery
Mark D. Neuman, MD, MSc; Paul R. Rosenbaum, PhD; Justin M. Ludwig, MA; Jose R. Zubizarreta, PhD; Jeffrey H. Silber, MD, PhD
JAMA. 2014;311(24):2508-2517

The investigators conducted a matched retrospective cohort study involving patients 50 years or older who were undergoing surgery for hip fracture at general acute care hospitals Of 56729 patients, 15904 (28%) received regional anesthesia and 40825 (72%) received general anesthesia. Overall, 3032 patients (5.3%) died in New York State between July 1, 2004, and December 31, 2011.

To go beyond prior observational studies, they used 2 statistical techniques intended to address selection bias, multivariable matching, and instrumental variable analysis. They hypothesized that regional anesthesia would be associated with improved outcomes compared with general anesthesia.

The near-far matched analysis showed no significant difference in 30-day mortality by anesthesia type among the 21514 patients included in this match
Regional anesthesia was associated with a 0.6-day shorter length of stay than general anesthesia

Thursday, June 26, 2014

Monitoring temperature in children undergoing anaesthesia: a comparison of methods

 TFE Drake-Brockman, M Hegarty, NA Chambers, BS von Ungern-Sternberg

 Anaesthesia and Intensive care

Volume 42, Issue 3 May 2014,315-320

Children undergoing anaesthesia are prone to hypothermia. Perioperative monitoring of patient temperature is, therefore, standard practice. Postoperative temperature is regarded as a key anaesthetic performance indicator in Australian hospitals. Many different methods and sites of temperature measurement are used perioperatively. It is unclear to what degree these methods might be interchangeable. The aim of this study was to determine the relationships between temperatures measured at different sites in anaesthetised children. Two hundred children, 0 to 17 years, undergoing general anaesthesia for elective non-cardiac surgery, were prospectively recruited. Temperature measurements were taken in the operating theatre concurrently at the nasopharynx, tympanic membranes, temporal artery, axilla and skin (chest). Patient age and weight were documented. Temperatures varied according to site of measurement. 

The mean difference from nasopharyngeal temperature to temperatures at left and right tympanic, temporal, axillary and cutaneous sites were +0.24°C, +0.24°C, +0.35°C, -0.38°C and -1.70°C, respectively.

 Levels of agreement to nasopharyngeal temperature were similar at tympanic, temporal and axillary sites. Tympanic and temporal temperatures were superior to axillary temperatures for detection of mild hypothermia (<36°C). Skin temperature showed a large variation from nasopharyngeal measurements. Our findings indicate that measured temperatures vary between sites. Understanding these variations is important for interpreting temperature readings.  

The use of a nasogastric tube to facilitate nasotracheal intubation: a randomised controlled trial

 C.-W. Lim,S.-W. Min et al

Anaesthesia

Volume 69, Issue 6, pages 591–597, June 2014

During nasotracheal intubation, the tracheal tube passes through either the upper or lower pathway in the nasal cavity, and it has been reported to be safer that the tracheal tube passes though the lower pathway, just below the inferior turbinate. We evaluated the use of a nasogastric tube as a guide to facilitate tracheal tube passage through the lower pathway, compared with the ‘conventional’ technique (blind insertion of the tracheal tube into the nasal cavity). A total of 60 adult patients undergoing oral and maxillofacial surgery were included in the study. In 20 out of 30 patients (66.7%) with the nasogastric tube-guided technique, the tracheal tube passed through the lower pathway, compared with 8 out of 30 patients (26.7%) with the ‘conventional’ technique (p = 0.004). Use of the nasogastric tube-guided technique reduced the incidence and severity of epistaxis (p = 0.027), improved navigability (p = 0.034) and required fewer manipulations (p = 0.001) than the ‘conventional’ technique

Sunday, June 22, 2014

Increased risk of acute kidney injury associated with higher infusion rate of mannitol in patients with intracranial hemorrhage
Clinical article
Min Young Kim ,MD et al

Journal of Neurosurgery

Jun 2014 / Vol. 120 / No. 6 / Pages 1340-1348 
 The objectives of this study were to assess the impact of mannitol on the incidence and severity of acute kidney injury (AKI) and to identify risk factors and outcome for AKI in patients with intracranial hemorrhage (ICH).
 The authors retrospectively evaluated 153 adult patients who received mannitol infusion after ICH between January 2005 and December 2009 in the neurosurgical intensive care unit.
 The overall incidence of AKI among study participants was 10.5% 
(n = 16). 
Acute kidney injury occurred more frequently in patients who received mannitol infusion at a rate ≥ 1.34 g/kg/day than it did in patients who received mannitol infusion at a rate < 1.34 g/kg/day.
 A higher mannitol infusion rate was associated with more severe AKI. Independent risk factors for AKI were mannitol infusion rate ≥ 1.34 g/kg/day, age ≥ 70 years, diastolic blood pressure (DBP) ≥ 110 mm Hg, and glomerular filtration rate < 60 ml/min/1.73 m2

Low intraoperative tidal volume ventilation with minimal PEEP is associated with increased mortality

 P. J. McCormick et al .

 BJA,Volume 113,Issue 1 Pp 07-108,July 2014


Anaesthetists have traditionally ventilated patients' lungs with tidal volumes (TVs) between 10 and 15 ml kg−1 of ideal body weight (IBW), without the use of PEEP. Over the past decade, influenced by the results of the Acute Respiratory Distress Syndrome Network trial, many anaesthetists have begun using lower TVs during surgery. It is unclear whether the benefits of low TV ventilation can be extended into the perioperative period.

Methods We reviewed the records of 29 343 patients who underwent general anaesthesia with mechanical ventilation between January 1, 2008 and December 31, 2011. We calculated TV kg−1 IBW, PEEP, peak inspiratory pressure (PIP), and dynamic compliance. Cox regression analysis with propensity score matching was performed to examine the association between TV and 30-day mortality.

Results Median TV was 8.6 [7.7–9.6] ml kg−1 IBW with minimal PEEP [4.0 (2.2–5.0) cm H2O]. A significant reduction in TV occurred over the study period, from 9 ml kg−1 IBW in 2008 to 8.3 ml kg−1 IBW in 2011 (P=0.01). Low TV 6–8 ml kg−1 IBW was associated with a significant increase in 30-day mortality vs TV 8–10 ml kg−1 IBW: hazard ratio (HR) 1.6 [95% confidence interval (CI) [1.25–2.08], P=0.0002]. The association remained significant after matching: HR 1.63 [95% CI (1.22–2.18), P<0.001]. There was only a weak correlation between TV kg−1 IBW and dynamic compliance (r=−0.006, P=0.31) and a weak-to-moderate correlation between TV kg−1 IBW and PIP (r=0.32 P<0.0001).


Conclusions Use of low intraoperative TV with minimal PEEP is associated with an increased risk of 30-day mortality.