Tuesday, November 24, 2015
Severe pain ( > 4 on a 0–10 scale) is commonly experienced during the first 48h with an incidence of nearly 70% on the first postoperative day and 48% on the second postoperative day
Women, younger patients and patients who required opioid analgesics preoperatively report significantly greater levels of postoperative pain
Infratentorial procedures are associated with more severe pain than supratentorial procedures
Reduced pain has been reported with a translabyrinthine as opposed to a suboccipital approach for acoustic neuroma resection
The amount of muscle damage from resection of the temporalis and posterior cervical muscles may also influence the degree of postoperative pain
Preoperative Gabapentin, parecoxib and lornoxicam may reduce opiate-induced hyperalgesia
the addition of ondansetron to PCA has not been shown to reduce nausea and vomiting after craniotomy
evidence suggests that NSAIDs should be stopped prior to neurosurgery and avoided in patients with cardiovascular disease.
Gabapentin given 7 days prior to surgery results in significantly lower postoperative pain scores and morphine consumption during the first 48 postoperative hours compared to phenytoin
Preoperative use of nerve blocks or local anesthetic infiltration reduces intraoperative analgesic requirements and may help to reduce pain in the early postoperative period
#craniotomy , #painmanagement, #painaftercraniotomy , #analgesia , #anesthesia ,#neurosurgery
(Ref: Acute and chronic pain following craniotomy Alana M. Flexman, Julie L. Ng and Adrian W. Gelb, Current Opinion in Anaesthesiology 2010, 23:551–557)
Saturday, November 21, 2015
✍Clinical euvolemia, hypotonic plasma, and less than maximally dilute urine are the clues
✍establish normovolemia by physical examination.
(Patients with SIADH are usually said to have normal volume status. However, they actually have excessive TBW. Unlike excessive saline, which is limited to ECF, excessive water distributes two thirds to the ICF and one third to the ECF. Thus the ECF excess is minor and not usually perceptible by clinical examination. Nonetheless, patients with SIADH have mildly increased ECV, which is sensed by the kidney. The kidney increases GFR, which causes a low uric acid, BUN, and creatinine. The increased ECV also increases ANP and, along with increased GFR, promotes natriuresis.)
✍measure P osm ,U osm ,P Na ,U Na , and U K .
✍exclude pituitary, adrenal, and thyroid dysfunction
✍Confirmatory criteria of SIADH include low P Na ( < 135 mEq/L), low P osm ( < 280mOsm/kg), U osm greater than 100mOsm/kg, U Na greater than 40mEq/L, and [U Na + U K ] greater than P Na .
#SIADH , #anesthesia
Friday, November 20, 2015
✔️Dantrolene inhibits calcium release via RyR1 antagonism and impairs calcium-dependent muscle contraction.
✔️This rapidly halts the increases in metabolism and secondarily results in a return to normal levels of catecholamines and potassium.
✔️Dose is 2 mg/kg; repeat every 5 minutes until vital signs normalise , to a total dosage of 10 mg/kg if needed.
✔️dantrolene takes ~ 6 minutes to have any effect
✔️The solution is prepared by mixing 20 mg of dantrolene with 3 g of mannitol in 60 ml of sterile water.
✔️Since dantrolene is relatively insoluble, preparation is tedious and time consuming, and its preparation should not be the responsibility of the primary anesthesiologist involved in the patient’s management. (May occupy several nurses)
✔️All patients who develop MH, require at least 24 hours of posttreatment management in a critical-care setting as there is chance of reappearance of symptoms ( known as recrudescence )
In the ICU, continue @1mg/kg q6h for 24 hours
may be given enterally if GIT functioning (price ~ 1000 x less)
✔️the actions of dantrolene include:
release of Ca ++ from the SR, without affecting re-uptake
? antagonises the effects of Ca ++ at the actin/myosin - troponin/tropomyosin level
muscular weakness, which may potentiate NMJ blockade ~ 5-15 mg/kg produces significant muscular relaxation
there is no effect on NMJ transmission
up to 15 mg/kg there is no significant effect on the CVS
up to 30 mg/kg there is no significant effect on respiration
#dantrolene , #MalignantHyperthermia, #mh ,#anaesthesia
Thursday, November 19, 2015
THE RIGHT WAY OF ADMINISTERING BLOOD PRODUCTS [ from "THE CLINICAL USE OF BLOOD: HAND BOOK , World Health Organization & Blood Transfusion Safety , GENEVA ]
✔️Prefer a larger cannula: A doubling of the diameter of the cannula increases the flow rate of most fluids by a factor of 16.
✔️In case of Whole blood, red cells, plasma and cryoprecipitate
>Use a new, sterile blood administration set containing an integral 170–200 micron filter
>Change the set at least 12-hourly during blood component infusion
>In a very warm climate, change the set more frequently and usually after every four units of blood, if given within a 12-hour period
✔In case of Platelet concentrates
>Use a fresh blood administration set or platelet transfusion set, primed with saline.
>There is no evidence that warming blood is beneficial to the patient when infusion is slow.
>At infusion rates greater than 100 ml/minute, cold blood may be a contributing factor in cardiac arrest. However, keeping the patient warm is probably more important than warming the infused blood.
>Warmed blood is most commonly required in:
Large volume rapid transfusions:
-Adults: greater than 50 ml/kg/hour -Children: greater than 15 ml/kg/hour
Exchange transfusion in infants
Patients with clinically significant cold agglutinins.
>Blood SHOULD ONLY BE WARMED in a blood warmer. Blood warmers should have a visible thermometer and an audible warning alarm and should be properly maintained.
>Blood should never be warmed in a bowl of hot water as this could lead to haemolysis of the red cells which could be life-threatening.
✔️Severe reactions most commonly present during the first 15 minutes of a transfusion. All patients and, in particular, unconscious patients should be monitored during this period and for the first 15 minutes of each subsequent unit.
✔️The transfusion of each unit of the blood or blood component should be completed within four hours of the pack being punctured. If a unit is not completed within four hours, discontinue its use and dispose of the remainder through the clinical waste system.
Tuesday, November 17, 2015
ADMINISTRATION ROUTES: IV, IM, SC, Intranasal DDAVP/Desmopressin
1. Treatment of central diabetes insipidus 2. Prevention and control of bleeding (primarily when there are thought to be platelet function defects especially uraemia, clopidogrel or cardiopulmonary bypass -related)
PRESENTATION AND ADMINISTRATION:
IV: Minirin 4mcg/ml injection Octostim 15mcg/ml injection Doses of 4mcg or less should be administered undiluted by direct IV injection. For small doses (eg 0.4mcg), 4mcg can be diluted in 10 ml of normal saline. For doses of greater than 4mcg in adults or children weighing more than 10kg, dilute with 50ml of normal saline and infuse the first 5ml slowly over 5 minutes. For children weighing less than 10kg, dilute in 10ml of normal saline and infuse the first 1-2ml over 5 minutes. If no marked tachycardia or other adverse effects are observed, give the remainder slowly over 15 minutes PO: Minirin 0.1mg tablets (white)
Nasal Spray: Desmopressin spray (10mcg/dose), Minirin spray (10mcg/dose), Octostim (150mcg/ dose)
IV: Central diabetes insipidus: 0.4mcg repeated as required (may increase the dose if there is an adequate response)
Prevention and control of bleeding: 0.3mcg/kg (max 24mcg) over 30 minutes (once only) Note: although IM and SC routes can be used, IV is generally the preferred route. PO: 0.1mg -1.2mg daily depending on indication (rarely used by this route in ICU)
Nasal Spray: Not generally administered by this route in ICU
No adjustments needed in CRF
CLINICAL PHARMACOLOGY: Desmopressin is a synthetic analogue of the natural pituitary hormone arginine vasopressin (ADH), an antidiuretic hormone affecting renal water conservation..
1. Hypersensitivity to desmopressin 2. Hyponatraemia
When desmopressin acetate injection is administered to patients who do not have need of antidiuretic hormone for its antidiuretic effect, in particular in paediatric and geriatric patients, fluid intake should be adjusted downward to decrease the potential occurrence of water intoxication and hyponatraemia.
Particular attention should be paid to the possibility of the rare occurrence of an extreme decrease in plasma osmolality that may result in seizures which could lead to coma.
Laboratory tests for monitoring the patient include urine volume and osmolality. In some cases, plasma osmolality may be required.
NB: may cause minor increases in blood pressure requiring changes in levels of vasopressor support.
transient headache, ischaemic stroke, changes in blood pressure causing either a slight elevation or a transient fall and a compensatory increase in heart rate, myocardial infarction, nausea, abdominal cramps, water intoxication and hyponatraemia,Local irritation at site of injection, thrombotic events
Monday, November 16, 2015
# Preoperative treatment with GnRH analogue to shrink the fibroid
# Surgeon may intraoperatively inject dilute Vasopressin ( 1 IU in 100 mL RL) to reduce bleeding. IV Vasopressin can cause raised BP, myocardial ischemia, arrhythmias etc
# Position: Dorsal lithotomy; steep Trendlenberg to move the bowel out of surgical field
# Surgical time :1-4 hours; EBL: 100-600 mL
Puncture of major vessel/ severe bleeding
Insufflation in the wrong place
Need for conversion to laparotomy
Peroneal nerve damage from positioning
# Pain score : 4-6
#laparoscopy,#laparoscopyanaesthesia,#myomectomy, #anaesthesia, #anaesthetist
Sunday, November 15, 2015
The plastic components of the bypass circuit can sequester varying amounts of intravenous anesthetic agents resulting in unpredictable effects and side effects
Volatile anaesthetics are not usually available on ECMO circuits due to the difficulties in scavenging
Since anesthetic agents can alter preload and afterload, should be ready for volume replacement and administration of vasoactive agents
Should inform the perfusionist before changing the height of the surgical table, as this can alter the venous return to the ECMO circuit ( passive gravity assisted drainage)
Saturday, November 14, 2015
ATROPINE ; A VERY FAMILIAR ?STRANGER!
Atropine produces complete vagal block at a dose of 3 mg;
should be avoided in pyrexial children, as it inhibits sweating ;
delirium is another side-effect ;
patients with Downs syndrome may show resistance to atropine;
parenteral atropine wont cause significant pupillary dilatation and so is not contraindicated in glaucoma.
Thursday, November 12, 2015
Follow up the patient:
If voice is not improving: (Better to call the ENT Surgeon to do this-) Do a laryngoscopy and using any instrument, just give a mild pressure on aretynoid; usually it will fall back to correct position.
If speech is improving, advice VOCAL CORD ADDUCTION EXERCISES
Standing position.. Take a deep inspiration
and stop..and hold the breath.. this closes glottis..now strongly fall over and push against a wall...keep it for a few seconds.. Repeat this a few times.. This can force the aretynoid back to normal position by a stretching force... Usually voice is regained by this after 2 days..
Or lift heavy weights after deep inspiration (not for CAD patients)
Plus continue Speech Therapy
Problem occurs, when Aretynoid dislocates, and nobody attempts to relocate it, and it get fixed in that position..