HOW TO WEAN AND WHEN?

A patient is considered fit for weaning from ventilator when he is conscious responsive and hemodynamically stable and when the pathology which necessitated mechanical ventilation has been resolved adequately.Improved patient outcomes and decreased costs are two benefits of implementing a protocol for early weaning from ventilator.A simplified approach to weaning off ventilator is described below.

1).Criteria to determine whether a patient can be given a trial of spontaneous breathing.
Repiratory criteria:

• PaO2 > 60 mmHg on Fio2 40-50% and peep less than 5-8 cmH2O
• PaCO2 normal or baseline
• Adequate inspiratory effort

Cardiovascular criteria:

• No evidence of myocardial ischemia
• Heart rate less than 140/mt.
• Blood pressure normal without inotrops or minimal inotropic support eg: dopamine <5 mic/kg/mt

Adequate mental status:

• GCS >13 and arousable

Absence of correctable comorbid conditions:

• Afebrile
• No significant electrolyte abnormalities

2) Criteria to determine whether patients can tolerate spontaneous breathing trial

• Tidal volume               5-7 ml/kg                  threshold    >4-6 ml/kg
• Respiratory rate          10-18beats/mt          threshold    <30/mt.
• RR/VT ratio                20-40 /LTR                threshold 100/LTR
• Max insp. pressure     -90to -120 cm H2O     threshold  -15 to -30 cm H2O

The RR/VT ratio or rapid shallow breathing index is a useul predictor. Value above 105/LT, 95% of the attempts are successfull.

STRESS AND ANAESTHETIST

The previous night duty was so busy and i was tired out.The exploratory laparotomy went upto 2 am in the morning.Today i got up late and found my bus just leaving.My colleague staying next door offered me a lift but i reached hospital late.The morning ICU rounds already started and i tried to hide my self behind the team members, in order to escape notice of the consultant.The rounds finished and it was my turn to present the previous day's cases.It didnt go smooth as  I was drowsy  and was not able to concentrate. The consultant asked me to attend the elective  cases  in surgery OT where the list was also heavy with 3 major cases. While preparing for the cases, the  hospital clerk handed over  the university  notification for the venue and timings for final masters exam, scheduled  next month.The second case in my OT had a stormy recovery with laryngospam and agitation which was so difficult to control, and finally i am totally upset when the school principal telephoned and conveyed the message that my daughter is sick and will be brought to OPD.

Stress can be defined as mental, emotional or physical strain or tension which is an integral part of everyone's life.Even though moderate stress is necessary for the optimal function of human beings undue stress may have physiological and psychological impact(1) Stress occurs when there is a perceived imbalance between the demands being made and the ability to meet those demands.It is a pattern of strain produced by excessive urgency or pressure.  According to Cooper  stress is negatively perceived quality which could cause physical and mental ill health.

Most of the doctors are found to have Type A personality featuring insecurity of status and a high amount of anxiety. This personality type is often associated with increased aggression and a constant sense of time urgency and mental tension.They are more prone for stress related responses.They also tend to have a higher incidence of coronary artery disease and may have problems coping with and responding to difficult situations. This may lead on to psychiatric problems in the future.