Difficulties in recrutment

Chronically ventilated patients will be hemodynamically measured by bioimpedance (NiCAS by NI medical ltd.) for cardiac output, Total peripheral resistance and other NICAS derived parameters.

Patients fluid balance will be planned according to these parameters and the rate of liberation from ventilator and rate of worsening renal function will be measured

Patients will be divided into two groups , the study group and the control group randomly assigned by a computer program .

After obtaining written informed consent , cardiac monitoring will be carried out by means of a NiCAS patients in both groups.The physician will not be exposed to the measurement data of the patients in the control group. For the research group : Monitoring will be carried out once a day , preferably at the same time the first three days . An increase in time interval is possible in accordance with an improvement in the patient . Patients will be treated according to the protocol described in Figure 1. Also , a graphic description of the various treatment zones and the exclusion zone is presented in Figure 2 .

For the control group patients will be treated according to the usual ward protocols.

The basic rules are:

Avoiding over- drying by using parameter TBW .

• Avoidance of renal dysfunction by maintaining the cardiac output above 2.3 , and avoiding the use of beta-blocker overdose in cases of low cardiac output and bradycardia as a result of maintaining an average blood pressure over 70 .
• In cases of high peripheral resistance - Reduction of resistance while maintaining normal blood pressure .

Inclusion Criteria:

• All chronically ventilated patients (ventilated for more than 14 days)
• Age between 18-90

Exclusion Criteria:

• Non ventilated patient
• Total body water >80%