Experimental Design
The study is a Randomized control study. Consent forms were administered and consent obtained from clients in the antenatal clinic in their third trimester for booked clients and in latent phase for un booked clients who present to the labour ward. Volunteers or consenting women were randomly assigned into one of three groups as they present in the labour ward. Randomization was carried out in the labour ward during obstetrics triage using a computer-generated random number chart. The groups were randomly assigned to numbers (1 - 126). The clients picked one small envelop from a pool of randomly arranged small envelops. Each small opaque and sealed envelope contained a concealed number on paper. Matching for parity was done across the groups to improve validity.
Maternal blood samples were taken in for routine labour investigation mainly Haemoglobin concentration, grouping and cross matching, retroviral screening in EDTA bottle. The samples were taken to haematology laboratory for the tests. Estimation of blood urea nitrogen was done to objectively identify those with renal disease and dehydration and to exclude them from the study. Individuals excluded were managed accordingly. Plain sample bottle was used. The sample was transported to chemical pathology laboratory for analysis. A wide bore canula was placed in-situ for intravenous access.
The participants were randomized into group 1 which received unrestricted oral intake. Oral fluid was given to clients on demand. The group was considered as the control group (Positive control) based on WHO standard and recommendation for intrapartum care. 3 Oral fluid was administered on demand in a 250 mls graduated cups and amount taken recorded on a proforma. Water and beverages were allowed.
The participants randomized into groups 2 and 3 group had unrestricted oral fluid on demand as those in group 1. In addition, intravenous infusion of Ringer’s lactate solution at rates of 120 mls per hour and 240 mls per hour respectively were administered. Oral fluid taken was be recorded and added to the total amount infused intravenously.
The flow of Ringer’s lactate was controlled and regulated using gravitational method at rates of 40 drops per minutes and 80 drops per minutes for groups 2 and 3 respectively making it 120 mls per hour and 240 mls per hour respectively.
Partograph was used to monitor fetal heart rate, membrane status, cervical dilation, effacement, station of the presenting part, uterine contraction, maternal pulse, respiratory rate, maternal blood pressure, maternal temperature, drugs given and their doses. Amniotomy was performed when cervical dilatation reaches 5 cm and membranes intact. Amniotomy was performed with the aid of a plastic amniotomy hook following vaginal examination to exclude cord presentation. Immediately after each amniotomy, fetal heart rate was checked to with the aid of a sonicaid to determine fetal wellbeing and labour monitored. However, if after an hour of amniotomy, uterine contractions were found to be less than 3 in 10 minutes or cervical dilatation less than 1 - 1.2 cm per hour then the client is reviewed and labour augmented.
Oxytocin was used for augmentation any case of inefficient uterine contractions. oxytocin infusion drops were titrated and the total drops per minute were subtracted from the total drops of fluid to be administered as intravenous fluid to clients in groups (2 or 3). Such that if 40 drops per minute of ringer’s lactate is to be administered and 10 drops of oxytocin infusion, only 30 drops of ringer’s lactate were given simultaneously with 10 drops of oxytocin infusion. Such adjustments were done any time oxytocin drops were increased. These were done for those in groups 2 and 3 by opening another intravenous access any time the client required augmentation. The number of drops of the Ringer’s lactate infusion were delivered so that the total amount of fluid delivered by both oxytocin infusion and Ringer’s lactate infusion equals 120 ml/hour and 240 ml /hour for each group respectively at any time throughout the labour period. The amount taken orally was also recorded on a proforma for those in group 1 and the total amount delivered via infusion and that taken orally was summed for those in group 2 and 3 on the proforma. Also, whenever the client micturates, the urine is collected and measured in a calibrated urinal before discarding. The various volumes measured were summed and recorded as the total urine output for the client.
The duration of labour from 5 cm cervical dilatation to full cervical dilatation was considered as the duration of the 1st stage of labour for all groups and was recorded on the client’s proforma. The 2nd stage was from full cervical dilatation to delivery of the fetus and 3rd stage was from delivery of fetus to delivery of the placenta. The mouth and nose of a neonate were suctioned with a bulb suction indicated.
4.5 APGAR and Pulse Oximetry
After delivery, the cord was severed and the neonate handed over to the midwife in a clean warm towel. All neonates were wiped with the towel which stimulated them to increase activities. A neonatal pulse oximeter was placed on a foot to determine the oxygen saturation. APGAR scores were determined by the researcher and other trained research assistants. Research assistants mainly registrar cadre were recruited from each team of the department. They were trained in the labour ward by a neonatologist. The researchers had a picture aid and tabulated guide placed on the wall of labour ward to ensure accurate scoring. The scores were recorded on the proforma in the 1st ,5th and 10th minutes after delivery.
4.6 Samples collection for arterial cord blood gas analysis
Following delivery of the neonate the cord was clamped in two places about 5 - 10 cm away from the neonate with two clamps and divided in between the clamps with a cord scissors. The newborn will be handed over to midwife. With the aid of a 2 ml syringe the cord blood samples were taken about 3 - 5 cm below the clamp on the placental side of the cord. Following that another clamp was placed below the puncture site to prevent spillage of blood from the puncture site. All samples were taken from the umbilical artery which is one of the peripheral vessels of the umbilical cord. The blood sample was placed in lithium sample containers and analyzed immediately. Vacuum and blood collection tubes are not recommended and were not be used. The sampling procedure and administration of 10 IU intramuscular oxytocin were done within the first minute of the delivery of the fetus. The placenta was delivered by control cord traction. The birth canal was examined for bruises and lacerations. If episiotomy was given, it was repaired immediately.
4.7 Cartridge Loading
The sample was loaded onto a cartridge which contains electrochemical sensors that generate signals related to concentration levels of analytes in the blood. The cartridge contains 2.3 units of heparin for 1ml blood sample. The cartridge is able to aspirate up to 500 µL from 1 ml of sample.
The cartridge was then placed on the i15 blood gas and chemistry analysis system version 2.0 by EDAN instruments (MPN:01.54.455691020, P/N01.54.455691). The device is a portable automated system with a display screen, capable of storing information and transmitting it to other storage facility for data. It measures pH, metabolites (glucose, lactate), blood gases (PCO2, PO2), electrolytes (Na++, K+, Ca++, Cl-) and haemotocrit. It analyzes and stores the data or print out the results depending on the setting.
4.8 a. i-STAT 1 Analyzer
Early in the research, while using Edan i15 analyzer, the machine broke down. The machine was immediately replaced with a highly sensitive, point-of-care blood gas analyzer that delivers laboratory quality diagnostic results within two minutes. The new machine that was used is called iSTAT-1 produced by Abbott point of care incorporated Princeton United States of America.
It uses biosensor technology, advanced microfluidics and automated calibration. About two to three drops of blood sample are placed directly from the sampling syringe is placed into a small well on the cartridge. The well lid is closed and the cartridge is loaded unto the machine. As a compulsory safety check the machine must be on and the LOT-number of the cartridge to be used must be scanned by the machine before loading and recognizing the cartridge. There are different types of cartridges that are compactable with iSTAT 1. There are categorized based of the analytes there are capable of measuring. In this research, CG4+ cartridge was used. It analyses pH, lactate, pCO2, pO2, TCO2, HCO3, BEecf, sO2. All were recorded but for the purpose of this research, pH, lactate and SPO2 were recorded on the proforma. All other variables measured were stored in the memory of the machine for onward transmission and storage.
4.9 Method of Data Analysis