additional attribute to the publish method is
(PECL amqp >= Unknown)
AMQPExchange::publish — Publish a message to an exchange.
Publish a message to the exchange represented by the AMQPExchange object.
The message to publish.
The routing key to which to publish.
One or more of AMQP_MANDATORY and AMQP_MANDATORY.
Returns TRUE on success or FALSE on failure.
Throws an AMQPExchangeException on failure.
to send custom headers, you need send it as associative array under attribute 'headers'