Friday 6 September 2013

Supplementary Oxygen

NPO2
1L - increased FiO2 by 4%

Simple face mask
6-10L ~ 35-60%

VM 30-60%

HFM 02 ~ 10-15L/min
rebreathing 70-80%
non-rebreathing 95-100%

Ventilator Setting


Conventional Ventilator
PIP 18-20
PEEP
5-6 (diseased)
3-4 (normal)
I.T 0.35-0.45
Rate 40-60
         
If ↑ PCO2 
-↑PIP
-↑rate

If ↓ PO2
-↑PIP
-↑FiO2 --> ↑flow / PEEP

If PCO2 ↑ + PO2 ↓ --> ↑PIP

PCO2
Normal 35-45
Permissive 50-60
 (to prevent pneumothorax PCO2>45

Tissue damage if PO2 <30
Acceptable if SPO2 88-94%  

HFOV
If PCO2
 - amplitude
- frequency

If PO2
- mean
- FiO2
- frequency

Frequency
-term 9-10
-prem 11-12

Vt
Normal 1ml/kg
Diseased 1.6-2.0ml/kg
(achieved by ↑ mean)
Chest wriggle - amplitude

Sunday 18 August 2013

AEBA


Drugs

Bricanyl (terbutaline) - selective beta 2 agonist
SC bricanyl 0.5mg (1 ampule)
Infusion: 3.0mg (6 ampules) in 50cc NS - run 3ml / H

Salbutamols sulfate - 1 ampule = 1ml = 500mg

subcutaneous
 8mcg/kg 4 hourly
adult 250mg = 0.5ml

Infusion
 5-20mcg/min
 3mg (6ampule) in 50cc D5%
 1ml/h = 1mcg/min

MgSO4
2.47g (1ampule) in 5ml
2.0g slow bolus (4ml MgSO4 dilute in 46cc NS - run 50cc over 10-20min)  



Wednesday 24 July 2013

Rapid Sequence of Intubation (RSI)

Definition
administration of potent induction agent
after pre-oxygenation
followed immediately by rapidly acting neuromuscular blocking agent
to induce unconscious and motor paralysis  for tracheal intubation
without interposed positive airway ventilation

7 P's
1. Preparation
2. Pre-oxygenation
3. Pre-treatment
4. Paralysis with induction
5. Positioning
6. Placement with proof
7. Post-intubation management

A. Preparation

Prepare yourself, staffs, equipments

 MALES + 4 S

Mask
Airways
Laryngoscope
ETT

4 S's
 
4 S's
Suction
Stylet
Stethescope
Syringe



MARBLES x 2 is an alternative for the equipment and planning:

·         Masks (NP, NRB, BVM) and monitoring

·         Airway adjuncts (e.g. OPA, NPA, LMA) and Ask for difficult airway trolley

·         RSI drugs and Resus drugs

·         BVM and Bougie

·         Laryngoscopes

·         ETT and ETCO2

·         Suction and State Plan

Monitoring - cardiac, BP, pulse oxymetry
IV line - at least 1, preferably 2
Pharmacological agent - labeled
Laryngoscope
Suction
ETT - cuff tested for leak
Stylet
Ambu bag
LMA
Stethescope
Achoring tape
Ryle's tube

B. Pre-oxygenation
Principle
establishment of oxygen reservoir within the lung, blood and body tissue
to permit several minutes of apnoea
without arterial oxygen desaturation

Principle reservoir - functional residual capacity (FRC) ~ 30ml/kg

Method
Administration of 100% oxygen for 3 minutes
replaces predominantly nitrogenous mixture of room air with oxygen
allowing several minutes apnea time before Hb saturation <90%

C. Pre-treatment
administration of drugs to mitigate adverse effects associated with the intubation or patient's underlying comorbidities.
Adverse effects include
1. Bronchospastic reactive airway
2. Increased ICP
3. Reflex sympathetic response to laryngoscopy (RSRL)

Pre-treatment Drugs
Fentanyl       1mcg/kg over 30-60 sec
Lignocaine   1.0-1.5ml/kg

D. Paralysis with Induction
Administration of rapidly acting induction agent in a dose adequate to produce prompt LOC
immediately followed by neuromuscular blocking agent

Induction agents
1. Midazolam      0.1-0.5mg/kg
2. Ketamine         2.0mg/kg
3. Etomidate        0.3mg/kg
4. Propofol          2.0-2.5mg/kg

Ketamine
Adv    : good bronchodilator, use in severe hypotension/shock
Disad  : Increased BP/HR/ICP/muscle tone/salivation/intraoccular pressure, readily cross placenta

Etomidate
Adv     : Very cardiostable - used in cardiac patient and haemodynamically unstable ptx
Disad   : Suppresion of synthesis of cortisol with infusion

Propofol
Adv      : Conscious sedation
Disadv : Depression of cardiovascular / repiratory system, allergic reaction

Neuromuscular blocking agents
1. Scolene (suxamethonium / succinylcholine) - depolarising muscle relaxant
          Adult           1mg/kg
          Children      2mg/kg
          Neonate       3mg/kg
    Onset :  within 60sec
    Duration : 3-5minutes
    Adverse effects
    - hyperkalaemia (increased by 0.5mmol/l)
    - Bradycardia
    - malignant hyperthermia
    - increased ICP/IOP

2. Esmeron (recuronium) - non-depolarising muscle relaxant
          Dose            0.6-1.2mg/kg
     SE: hypokalaemia

Test for patient's jaw for flaccidity
~45sec after administration of scolene
~60sec after administration of rocuronium

If scolene is used, fasciculation will be observed

E. Positioning
 Sellick maneuvre (application of firm pressure on cricoid cartillage to prevent passive regurgitation)

F. Placement with proof
Direct visualisation
Calorimetric end tidal CO2 detector
Vapour in ETT
SPO2 monitoring
6 points auscultation
Chest rise


G. Post-intubation management
ETT anchoring
RT insertion - confirmed by rapid introduction of air in 10cc syringe with auscultation at epigastic
Hypotension -common, often caused by
1. Diminised venous return as a result of increased intra-thoracic pressure
2. Haemodynamic effects of induction agent
Self limited, respond to fluid resuscitation